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LESSONS 


IN 

EOR 

m 

THE  USE  OF  DISSECTORS. 


By  W.  E.  HORNER,  M.  D. 

ADJUNCT  PHOFESSOH  OP  ANATOMY  IN  THE  UNIVEHSITT  OF  PENNSTIVANIA,  ONE 
OF  THE  SURGEONS  OF  THE  PHILADEEPHIA  ALMS-HOUSE,  &C. 


SECOND  EDITION. 


PHILADELPHIA: 

H.  C.  CAREY  & I.  LEA— CHESNUT  STREET. 


18S7. 


/ 


\ 


■V: 


V\r  t /t  r 


Eastern  District  of  Pennsylvania,  to  wit; 

*********  BE  IT  REMEMBERED,  That  on  tlie  twenty-sixtli  day  of  June,  in 
* SEAi.  t the  forty -seventh  yeai’ of  the  Independence  of  the  United  States  of 
*********  America,  A.  D.  1823,  WiUiam  E.  Horner,  M.  D.  of  the  said  District, 
hath  deposited  in  this  Office  tlie  title  of  a Book,  the  right  whereof  he  claims 
as  author  in  the  words  following,  to  wit: 

“ Lessons  in  Practical  Anatomy,  for  the  Use  of  Dissectors.  By  W.  E.  Horner, 
“ M.  D.  Adjunct  Professor  of  Anatomy  in  the  University  of  Pennsylvania, 
“one  of  the  Surgeons  of  the  Philadelphia  Alms-House,  &c.” 

In  conformity  to  the  act  of  the  Congress  of  the  United  States,  entitled 
“ An  act  for  the  encouragement  of  learning,  by  securing  the  copies  of  maps, 
charts,  and  books,  to  the  authors  and  proprietors  of  such  copies  during  the 
times  therein  mentioned.”  And  also  to  the  act,  entitled  “An  act  supple- 
mentary to  an  act  entitled  ‘ An  act  for  the  encouragement  of  learning,  by 
securing  tlie  copies  of  maps,  chaiiis,  and  books,  to  the  authors  and  proprie- 
tors of  such  copies  during  the  times  therein  mentioned,’  and  extending  the 
benefits  thereof  to  the  arts  of  designing,  engraving,  and  etching  historic^  and 
other  prints.” 

(Signed)  D.  CALDWELL, 

Clerk  of  the  Eastern  District  of  Pennsylvania. 


PHILIP  S.  PHYSICK,  M.  D. 


PROFESSOR  OF  ANATOMY  IN  THE  UNIVERSITY  OF  PENNSYLVANIA. 

Dear  Sir, 

Permit  me  to  dedicate  to  you  this  little  work, 
proceeding  from  a course  of  Anatomical  Studies,  in 
which  your  patronage  has  been  incessantly  active,  and 
which,  without  your  disinterested  protection  and  en- 
couragement, might  probably  have  long  since  been 
relinquished.  I consider  it  a feeble  and  insufficient 
testimony  of  the  large  debt  of  gratitude  that  I owe 
you,  and  wish  that  it  was  more  worthy  of  your ‘notice; 
however,  as  it  is  the  best  at  present  in  my  power,  I 
hope  that  it  will  be  accepted  in  the  sense  in  which  it  is 
offered.  That  a life  so  usefully  employed  as  yours  in 
mitigating  the  ills  of  human  existence,  and  in  enlarging 
the  boundaries  of  the  science  of  medicine,  may  be 
protracted  through  a long  series  of  years  with  undi- 
minished physical  and  mental  vigour,  is  the  sincere 
prayer  of. 

Dear  Sir, 

Your  Obedient  Servant, 

W.  E.  HORNER. 


Philadelphia,  July  1st,  1823. 


https://archive.org/details/lessonsinpractic01horn 


CONTENTS 


Page 

Preface,  vii 

Introduction — On  Dissecting,  and  on  the  method  of  making  Ana- 
tomical Preparations,  . . - - - xv 

PART  I. 

Op  the  Head  and  Neck,  .....  i 

Chap.  I.  External  Parts  of  the  Head  and  Neck,  - - 1 

Sect.  I.  Of  the  Muscles  and  Fascise  of  the  Head  and  Neck,  2 

II.  Of  the  Glands  of  the  Head  and  Neck,  - - 23 

III.  Of  the  Blood  vessels  of  the  Neck  and  Head,  - 29 

IV.  Of  the  Nerves  of  the  Head  and  Neck,  - - 38 

Chap.  II.  Of  the  Internal  Parts  of  the  Head  and  Neck,  - - 60 

Sect.  I.  Of  the  Brain  and  Spinal  Marrow,  - - - 50 

II.  Of  the  Brain  and  Spinal  Marrow  according  to 

Gall  and  Spurzheim,  - - - - 75 

III.  Of  the  Eye,  - - - - - - -110 

IV.  Of  the  Ear, 127 

V.  Of  the  Nose,  140 

VI.  Of  the  Mouth, 144 

VII.  Of  the  Pharynx  and  (Esophagus,  ...  149 

VIII.  Of  the  Larynx,  - - - - - -153 

PART  II. 

Of  the  Trunk,  ......  163 

Chap.  I.  Of  the  Thorax,  .....  153 

Sect.  I.  Of  the  Muscles  in  front,  and  on  the  sides  of  the 

Thorax,  ....  163 

II.  Of  the  Viscera  of  the  Thorax,  - - 166 

Chap.  II.  Of  the  Abdomen,  ....  is9 

Sect.  I.  Of  the  Muscles  of  the  Abdomen,  - - 190 

II.  Of  the  Parts  concerned  in  Inguinal  Hernia,  201 

III.  Of  the  Parts  concerned  in  Femoral  Hernia,  209 

IV.  Of  the  Contents  of  the  Abdomen,  - - 218 

V.  Of  the  Diaphragm,  &c.  - - - 255 


VI 


CONTENTS. 


Page 

Chap.  III.  Of  the  Male  Pelvis,  ....  260 

Sect.  I.  Of  the  Viscera  of  the  Male  Pelvis,  - - 261 

II.  Of  the  Perineum  and  the  Fascia  of  the  Male 

Pelvis,  - - - - - 281 

Chap.  IV.  Of  the  Organs  in  the  Female,  for  the  Generation  and 

Nourishment  of  the  Infant,  - - 295 

Sect.  I.  Of  the  Female  Pelvis,  ...  295 

II.  Of  the  Female  Mamma,  ...  300 

Chap.  V.  Of  the  Nerves  and  Vessels  of  the  Trunk,  - . - 314 

Sect.  I.  Of  the  Nerves,  ....  314 

II.  Of  the  Blood  vessels,  ...  323 

III.  Of  the  Thoracic  Duct,  ...  335 

Chap.  VI.  Of  the  Muscles  of  the  Back,  ...  338 

PART  III. 

Of  the  Extremities,  .....  353 

Chap.  I.  Of  the  Upper  Extremities,  ...  353 

Sect.  I.  Of  the  Fascia,  ....  353 

II.  III.  Of  the  Muscles,  ...  354 

IV.  Of  the  Blood  vessels,  ...  382 

V.  Of  the  Nerves,  ....  397 

Chap.  II.  Of  the  Lower  Extremities,  ...  406 

Sect.  I.  Of  the  Fascia,  ....  406 

II.  Of  the  Muscles,  ....  409 

III.  Of  the  Blood  vessels,  - - - 440 

IV.  Of  the  Nerves,  - - - - 454 

PART  IV. 

Of  the  Ligaments,  .....  466 

Chap.  I.  Ligaments  of  Trunk,  ....  456 

Sect.  I.  Ligaments  of  Head  and  Spine,  - - - 466 

II.  Ligaments  of  Thorax,  ....  470 

III.  Ligaments  of  Pelvis,  - - - - . 472 

Chap.  II.  Ligaments  of  the  Upper  Extremities,  - - 475 

III.  Ligaments  of  the  Inferior  Extremities,  - - 482 

PART  V. 

Of  the  Integuments,  - - - - - 491 

Chap.  I.  Skin,  . .....  491 

II.  Hair,  ......  495 

HI.  Nads,  ......  496 

IV.  Sebaceous  Organs,  ....  496 

Index,  .......  497 


PREFACE. 


\ 


The  following  sheets  were  put  together  with  a hope 
of  their  contributing,  in  some  measure,  to  facilitate 
the  most  dijSicult  and  important  part  of  a medical 
education,  the  study  of  Anatomy.  They  are  the  result 
of  many  dissections  performed  in  the  course  of  ten 
years  by  myself,  and  by  the  young  men  who  have  con- 
fided in  me  by  submitting  to  my  instructions.  The 
arrangement  is  in  some  respects  unusual,  as  regards 
a work  on  Practical  Anatomy;  but  has  arisen  from 
much  reflection  on  the  subject,  and  from  a careful 
observation  of  that  course  which  students  are  most 
disposed  to  adopt  when  left  to  themselves.  There  are 
but  few  men  possessed  of  moderate  activity  of  mind 
who  do  not,  in  the  prosecution  of  a study  even  new  to 
them,  adopt  some  labour-saving  means,  overlooked 
and  sometimes  unknown,  to  such  as  are  much  further 
advanced.  It  has  happened  to  me  frequently,  while  su- 
‘ perintending  the  studies  of  others,  to  observe  this 


Vlll 


PREFACE. 


fact,  and  that  none  of  the  books  in  common  use  an- 
swered continually  for  reference;  either  in  conse- 
quence of  the  actual  plan  of  the  books  not  being 
suitable  to  the  course  of  dissections,  or  in  consequence 
of  the  partition  of  the  subject  among  several  students 
causing  the  dissection  of  one  person  to  interfere  with 
that  of  another.  The  idea  of  founding  a text-book 
to  suit  the  latter  arrangement,  was  thus  suggested ; and 
I trust  therefore  that  the  present  treatise  will,  in  most 
cases,  be  found  to  answer  either  where  several  students 
dissect  together  on  the  same  subject,  or  where  the 
student  dissects  alone  upon  a section  of  the  body. 

In  the  original  conception  of  the  work  it  appeared 
to  me  that  I might  introduce  advantageously  remarks 
on  Morbid  Anatomy,  on  Surgical  Operations,  and  on 
Physiology;  but  in  computing  the  number  of  pages 
that  the  descriptive  anatomy  alone  would  occupy,  I 
found  that  such  a mass  of  materials  would  become 
a system,  and  interfere  much  with  the  simplicity 
and  conciseness  that  I wished  to  predominate  in 
the  character  of  the  performance.  I have  therefore 
intentionally  indulged  very  seldom  in  such  remarks; 
but  in  case  of  the  present  effort  meeting  the  sanction 
of  public  approbation,  may  be  tempted  at  a future  day 


PREFACE. 


IX 


to  give  an  additional  volume  appropriated  to  these 
subjects.  As  the  introduction  of  such  observations 
is  very  common  in  manuals  of  Anatomy,  I will  state 
why  it  has  not  been  imitated  in  the  present.  In 
my  own  progress  as  a student,  I had  a hand-book  of 
the  kind,  but  it  very  frequently  happened  that  the 
subject  I was  engaged  in  dissecting,  had  none  of  the 
diseases  or  morbid  appearances  that  the  page  I was 
reading,  referred  to.  The  author  indeed  seemed  to 
labour  under  the  presumption  that  the  young  anatomist 
was  working  on  just  such  a subject  as  he  had  in  view; 
and  therefore  blended  his  morbid  and  descriptive 
anatomy  so  much  by  alternate  sentences  for  each, 
and  sometimes  in  the  same  sentence,  that  the  eye  could 
not,  without  much  trouble,  distinguish  what  was  want- 
ed. A positive  inconvenience  was  thus  sustained.  In 
regard  to  surgical  operations,  the  young  student  seldom 
performs  them  in  his  first  period  of  (^ssections;  his 
mind  is  closely  and  laboriously  occupied  in  pursuing 
the  dissection,  in  getting  out  the  parts  properly,  and 
he  thinks  he  has  quite  enough  to  do  in  following  the 
most  simple  description.  As  regards  physiology,  the 
reasons  just  stated  must  apply  with  more  force  to  it. 

I do  not  wish  to  be  understood  as  assigning  a diminished 

b 


X 


PREFACE. 


importance  to  Morbid  Anatomy,  on  the  contrary,  I 
have  the  highest  opinion  of  its  value,  as  the  whole  prac- 
tice of  medicine  is  founded  on  it;  I mean  only  that  a 
text-book  for  young  students  should  present  the  task 
of  Anatomy  in  its  most  simplified  form.  When  the 
parts  become  familiar  and  well  understood  by  frequent 
dissection,  the  advanced  student  may  then  draw  in  as 
many  collateral  branches  as  he  chooses,  and  he  will 
never  attempt  it  without  pleasure  and  instruction.  At 
this  point  any  of  the  treatises  on  surgery,  morbid  ana- 
tomy, and  physiology  will  answer  his  purpose. 

I have  been  concise  on  another  subject:  Directions 
how  to  proceed;  to  which  some  Anatomists  give  the 
highest  importance,  so  high  indeed  that  in  many  in- 
stances the  subject  matter  is  lost  in  the  directions  how 
it  is  to  be  found  out.  In  the  opinions  of  some,  I may 
here  have  fallen  into  error:  my  general  intention  has 
been,  in  all  cases,  to  assist  by  directions  where  the 
novelty  and  obscurity  of  the  operation  left  no  clew  for 
the  student;  but  where  the  dissection  or  mode  of  ex- 
amination was  a plain  appeal  to  common  sense,  con- 
nected with  common  powers  of  vision,  I have  thought 
it  superfluous,  and  even  ridiculous  to  write  down  what 


PREFACE. 


XI 


was  to  be  done.  In  the  common  operation  of  walk- 
ing, it  would  be  quite  philosophical  to  tell  a being  of 
another  world,  who  knew  nothing  of  this,  and  was 
differently  constituted,  that  it  was  accomplished  by 
putting  one  leg  before  the  other ; but  perhaps  there  is 
no  human  being,  in  the  rational  exercise  of  his  facul- 
ties, who  would  thank  any  one  for  such  information. 
On  this  ground  I have  omitted  many  directions;  but 
it  is  not  improbable  that  things  which  seem  perfectly 
plain  and  appreciable  to  one  in  the  daily  exercise  of 
Anatomy,  may  be  more  obscure  to  another  less  oc- 
cupied with  it. 

It  will  be  seen  that  the  work  consists  of  three  Parts 
the  Head  and  Neck,  with  the  contained  organs,  form 
one  part,  the  Trunk  a second,  and  the  Extremities  a 
third.  The  division  is  obviously  artificial,  as  probably 
every  other  plan  must  be  ; for  in  following  the  details 
of  Anatomy,  it  is  impossible  to  avoid  chasms  in  the 
description.  The  human  body  is  a whole,  but  made 
up  of  such  a multitude  of  parts  that  no  mind  can  com- 
prehend or  receive  at  once  all  of  them.  In  this  di- 

^ This  arrangement  has  been  slightly  altered  in  the  second 
edition  but  not  in  such  a way  as  to  affect  the  general  plan  of  the 
work. 


XII 


PREFACE. 


lemma,  each  writer  will  probably  have  an  arrange- 
ment, which  to  him,  appears  better  than  all  others. 
It  may  be  asked,  why  I have  put  the  most  difficult 
part  of  Anatomy  first?  I answer,  that  it  is  only  first 
to  him  who  chooses  to  study  it  first.  The  plan 
of  the  book  enables  the  student  to  commence  with 
either  of  the  parts,  with  nearly  equal  advantage.  In 
adopting  the  actual  arrangement,  the  most  prominent 
objection  in  my  mind  to  it,  was  the  necessity  of  repeat- 
ing the  same  observations  in  different  places.  In  writing 
I have  had  this  continually  in  view ; and  though  it  could 
not  always  be  avoided,  I have  nevertheless  endeavoured 
to  curtail  so  much  its  frequency,  that,  I trust,  it  will 
not  be  considered  a fault  of  much  magnitude. 

In  regard  to  recent  observations  in  Anatomy,  I have 
for  the  most  part  quoted  them  when  they  were  of 
such  a cast  as  to  be  comprehended  in  the  general  ob- 
ject of  the  work.  I have  also  added  a few  new  things 
of  an  original  character  with  myself ; they  consist  prin- 
cipally in  a muscle  at  the  inner  canthus  of  the  eye, 
not  heretofore  described;  and  in  an  explanation  of  the 
method  of  closing  the  upper  part  of  the  glottis  in 
swallowing  or  vomiting,  not  commonly  given  by 
physiologists. 


PREFACE. 


xiii 

It  may  be  asked  why,  with  such  a quantity  of  simi- 
lar works  in  circulation,  I have  taken  the  trouble  to 
write  this?  I reply  candidly,  because  I think  their 
plans  and  manner  of  execution  do  not  hit  precisely  the 
case  for  which  they  are  intended.  I have  however 
neither  the  disposition  or  intention  to  decry  them, 
because  my  own  ware  is  in  the  market.  I have  felt 
much,  their  value  in  many  respects,  and  take  pleasure 
in  giving  my  feeble  tribute  of  praise  to  the  works  of 
Messrs.  Fyfe,  Bell,  Shaw,  and  the  London  Dissector, 
among  the  English ; and  to  the  works  of  MM.  Mar- 
jolin  and  Maygrier,  among  the  French.  On  the  sub- 
ject of  Hernia,  I am  much  indebted  to  Sir  Astley 
Cooper  and  to  Mr.  Laurence.  On  the  Anatomy  of 
the  Pelvis,  to  Messrs.  Colles  and  Breschet.  Among 
the  Systematic  Treatises  on  Anatomy,  I owe  much 
to  Dr.  Wistar’s  System,  to  Bichat,  Sabatier,  Portal, 
Bell,  and  above  all  to  the  very  splendid  and  surpass- 
ing work  of  Antonius  and  Caldani  published  in  Ve- 
nice, which  contains  all  things  excellent  in  our  art, 
selected  from  Soemmering,  Loder,  Meckel,  Scarpa, 
Vicq.  D^Azyr,  the  Hunters,  Gall  and  Spurzheira,  &c. 
&c.,  which  was  put  into  my  hands  by  the  liberality  of 
Dr.  Physick. 


INTRODUCTION. 


On  Dissecting,  and  on  Anatomical  Preparations. 

The  dress  of  a student  of  anatomy  should  consist  of 
an  apron,  extending  from  the  neck  to  half-way  down 
the  legs;  and  of  a pair  of  sleeves,  attached  to  the  apron 
or  not,  according  to  the  fancy  of  the  wearer.  It  should 
be  so  loose  as  to  give  him  perfect  freedom  in  all  his 
motions.  The  instruments  are  contained  in  a box, 
called  a Dissecting  Case.  They  should  consist  of  four 
knives,  one  single  hook,  one  double  hook,  one  pair  of 
forceps,  one  pair  of  scissors,  one  blow  pipe,  and  two 
crooked  needles. 

Cleanliness  is  of  the  first  importance ; the  dissector 
should,  therefore,  never  suffer  his  table  to  become  foul 
from  blood  or  pieces  of  flesh  standing  on  it,  neither 
should  he  suffer  blood  to  remain  in  the  different  de- 
pressions about  the  subject,  when  it  can  be  conveni- 
ently got  out.  He  should  keep  a sponge  for  himself, 
for  v/here  a sponge  is  used  by  several  it  becomes 
nobody’s  business  to  clean  it ; the  consequence  is  that  it 
is  seldom  fit  for  use.  When  the  integuments  of  a sub- 
ject are  laid  open,  the  parts  exposed  either  dry  or 
putrefy  rapidly.  A constant  rule  is  hence  established 
not  to  turn  down  more  skin  than  the  freedom  of  dissec- 
tion requires,  and  to  save  it  as  much  as  possible  to  cover 


XVI 


INTRODUCTION. 


the  parts  again,  when  the  dissection  is  suspended  for  an 
interval.  When  there  is  not  enough  of  it  for  this  pur- 
pose, a damp  cloth,  several  folds  thick,  should  be  at 
hand  to  assist  in  covering. 

The  knife  should  be  held  like  a writing  pen  in  the 
right  hand ; when  muscles  are  dissected  it  should  be 
exclusively  used  for  cutting,  as  the  scissors  do  not 
answer.  The  integuments  or  the  parts  covering  the 
muscles,  should  be  held  perfectly  tense  with  the  other 
hand,  or  with  the  forceps.  The  knife  should  be  pass- 
ed with  a steady  and  light  stroke  in  the  direction  of 
the  muscular  fibres,  and  in  such  a way  as  just  to  graze 
them.  This  latter  rule  is  indispensable;  no  one  can 
dissect  a muscle  well  without  observing  it,  and  it  should 
be  continually  present  to  the  mind  of  the  student. 

OF  INJECTIONS.* 

There  are  three  kinds  of  injections  in  use  among 
anatomists,  the  Coarse,  the  Fine,  and  the  Minute; 
which  are  applied  to  the  filling  of  the  arteries  and  of 
the  veins,  in  order  to  demonstrate  their  courses  more 
satisfactorily. 

* Swammerdam  first  used  wax  injections  and  that  about  the 
year  1672.  Corroded  preparations  were  first  made  by  Francis 
Nicholls,  Professor  of  Anatomy  at  Oxford,  about  the  beginning 
of  the  last  century.  Rouhaut,  a surgeon  of  the  King  of  Sar- 
dinia, first  dissolved  glue  to  inject  small  vessels  with.  Hom- 
berg  of  Paris,  proposed  a mixture  of  equal  parts  of  tin,  bismuth 
and  brass,  wherewith  to  inject  blood-vessels  by  means  of  a pneu- 
matic apparatus  for  forcing  it  in. 


INTRODUCTION, 


xvii 


No.  I. 

For  Coarse  injection  take  the  following  ingredients : 

Y ellow  Bees-wax,  pure,  sixteen  ounces, 

Bleached  Rosin,  eight  ounces. 

Turpentine  Varnish,  by  measure,  six  ounces.* 

Or,  No.  IL 

Yellow  Resin,  two  pounds. 

Yellow  Wax,  one  do. 

Turpentine  Varnish,  a sufficient  quantity  to  make  the 
mixtxire  flexible  when  cold.t 

Or,  No.  III. 

Tallow,  two  pounds. 

White  Wax,  ten  ounces, 

Common  Oil,  six  ounces, 

Venice  Turpentine,  four  ounces.^ 

Mix  and  liquefy  them  over  a slow  jfire;  or^  what  is 
still  better,  in  boiling  water. 

For  making  either  mixture  red;  add  Vermilion  ^iij. 

do.  do.  yellow;  King’s  Yellow,  ^ijss. 

do.  do.  white;  Best  Flake  White,  §vss. 

* Fyfe,....Pole.  t Nicholls.  | Munro. 

c 


xviii 

INTRODUCTION. 

C Best  Flake  White,  5iijss. 
pale  blue;  ^ 

C Blue  Smalt,  ^ujss. 

do. 

do. 

do. 

do. 

, dark  blue;  Blue  Verditer,  gxss. 

do. 

do. 

black;  ■ Lamp-Black,  ^i. 

f Powdered  Verdigris,  ^ivss. 

do. 

do. 

green;  < Best  Flake  White,  ^iss. 
( Gamboge,  powdered,  ^i. 

No.  IV. 

For  Fine  injection  take  the  following: 

Brown  Spirit  Varnish,  ^iv. 

White  Spirit  Varnish,  ^iv. 

Turpentine  Varnis'h,  ^i. 

Mix  and  heat. 

To  make  this  mixture  red;  add  Vermilion,  ^i. 


do. 

do. 

yellow;  King’s  Yellow,  ^i^. 

do. 

do. 

white;  Best  Flake  White,  ^ij. 

do. 

do. 

, , , C Fine  Blue  Smalt,  5iss. 

* ^ Best  Flake  V lute,  jr 

do. 

do. 

dark  blue;  Blue  Verditer,  ^iv. 

do. 

do. 

black;  Lamp-Black,  jss. 

Or,  No.  V. 


According  to  Dr.  Munro,  a fine  injection  may  be  obtained,  by 
pouring  oil  of  turpentine  on  any  finely  powdered  colouring 
matter,  till  it  reaches  a proper  consistence. 


INTRODUCTION. 


JSIX 


No.  VI. 


For  Minute  injection  take  the  following : 

Most  Transparent  Glue,  broken  to  pieces,  or  Isinglass,*  §viij. 


Let  the  mixture  stand  till  it  is  dissolved,  which 
will  take  from  one  to  two  days.  Then  heat  it  gently 
till  it  is  uniform,  or  a perfect  size  is  made. 

To  make  this  mixture  red;  add  Vermilion,  5v. 


In  all  of  these  formulae  for  Injections,  it  is  of  the 
utmost  importance  to  success  in  throwing  them  in,  to 
have  the  colours  in  the  purest  condition  and  reduced 
to  the  finest  powder  by  levigation  or  trituration.  In 
Philadelphia  they  are  found,  for  the  most  part,  in  a 
state  fit  for  use  in  the  Druggist’s,  and  Painter’s  and 
Glazier’s  shops.  But  to  render  injection  still  more 

' The  Isinglass  is  much  more  expensive,  but  more  minute. 


Water, 


ifeiss. 


Mix. 


do.  do.  yellow;  King’s  Yellow,  ^iv. 

do.  do.  white;  Best  Flake  White,  ^v. 

do.  do.  blue;  Fine  Blue  Smalt,  ^viij. 


do.  do.  black;  Lamp-Black,  ^i. 


XX 


INTRODUCTION. 


certain  it  is  better  to  strain  the  mixtures  after  the 
colours  are  added,  through  a fine  flannel  cloth,  which 
will  arrest  the  impurities  both  in  the  original  mixture 
and  in  the  colouring  ingredients. 

No.  VII. 

A commodious  preparation,  and,  for  the  most  part,  a 
very  successful  one,  has  been  in  use  amongst  us  for 
many  years.  It  is  also  much  approved,  I have  un- 
derstood, in  other  parts  of  the  United  States,  and  is 
commonly  called,  the  Cold  Injection.  To  make  it,  take 

White  Lead  and  Red  Lead,  of  each  ^iv. 

Linseed  Oil  enough  to  form  a thick  paste  by  rubbing  them 
well  together.  Liquefy  this  paste  with  Turpentine  Varnish, 
^viii. 

Just  before  injecting  sprinkle  this  mixture  wuth  cold 
water.  The  advantage  of  it  is,  that  it  does  not  re- 
quire the  subject  to  be  previously  heated.  The  colour 
may  be  improved  with  vermilion.* 

These  ingredients  are  used  in  various  proportions  by 

* As  making  a mixture  for  each  time  one  has  to  inject  is 
rather  troublesome,  a larger  quantity  of  the  ingredients  with 
the  exception  of  the  vaimish  may  be  blended,  and  then  kept 
fluid  for  a long  period  by  pouring  water  into  the  vessel.  After 
the  varnish  is  once  added  the  mixture  must  be  used  immediately, 
as  it  then  begins  to  thicken. 


INTRODUCTION. 


XXI 


different  anatomists,  and  it  may  be  found  advantageous 
to  increase  or  diminish  their  relative  quantity  accord- 
ing to  circumstances.  The  Red  Lead  is  more  drying 
than  the  White,  and  is  sometimes  used  without  the 
other  as  follows: 

No.  VIIL 

Red  Lead.  • 

Linseed  Oil  sufi&cient  to  bring  it  to  tbe  consistence  of  putty. 

Then  equal  parts  of  Spirits  of  Turpentine  and  Turpentine 
Varnish,  until  it  is  reduced  to  a semifluid  state. 

Just  before  injecting  sprinkle  it  with  a little  water  and  stir  it.*' 

White  Lead,  treated  in  the  same  way  with  linseed 
oil  and  turpentine  varnish,  may  have  its  colour  chang- 
ed to  fancy  hy  any  of  the  colouring  matters  mentioned. 
It  is  not  necessary  to  strain  these  lead  mixtures. 

No.  IX. 

When  the  student  wishes  only  to  prosecute  the  dis- 
section of  the  vessels  without  making  a preparation  of 
them,  the  following  injection  will  answer. 

Tallow,  ibij. 

Turpentine  Varnish,  ^x. 

Red  Lead, 

Mix. 

This  mixture  retains  it  fluidity,  when  melted,  for 
a long  time,  and  may  be  thrown  from  the  arch  of  the 

Charles  Bell’s  system  of  Dissections,  London,  1809. 


XXll 


INTRODUCTION. 


aorta  through  the  primitive  and  many  of  the  secon- 
dary arterial  trunks,  without  heating  the  subject.  Its 
cheapness  makes  it  very  advantageous. 

The  success  of  this  injection  will  be  increased  by 
throwing  in  first,  a syringe  full  of  Nos.  IV.  or  V.  pro- 
perly heated,  with  a view  of  warming  somewhat  the 
vessels  and  removing  their  rigidity . 

In  the  use  of  these  formulae  excepting  Nos.  ATI.  ATII. 
and  IX.  it  is  indispensable  to  warm  the  subject  thoroughly 
by  previous  immei’sion  in  water  hot  enough  to  excite 
the  sensation  of  scalding  in  the  finger.  If  the  water 
be  warmer  it  will  cause  the  parts  to  contraet  and  be- 
come rigid  instead  of  softening  them.  The  injections 
must  be  of  a proportionate  temperature. 

The  more  limited  the  range  of  an  injection  is,  the 
more  likely  it  will  be  to  succeed  well,  as  the  force  of 
the  syringe  is  thereby  concentrated.  Hence  a rule  is 
established  to  put  the  pipe  as  near  as  possible  to  the 
part  intended  to  be  injected. 

No.  I.  is  used  for  corroded  and  dried  preparations. 
Nos.  II.  and  III.  for  the  latter  alone.  Nos.  IV.  and  V.  is 
sometimes  used  as  the  precursor  to  the  three  first. 
No.  AT.  is  adopted  in  wet  preparations  and  such  as  are 
intended  to  demonstrate  minute  vascularity.  Nos.  ATI. 
and  VIII.  answers  remarkably  well  for  dried  prepara- 


INTRODUCTION. 


xxiii 

tions ; it  takes  about  twenty-four  hours  to  harden ; the 
part  injected  should,  therefore,  not  be  disturbed  till 
the  expiration  of  that  period. 

The  student  acquainted  with  the  circulation  of  the 
blood  will  always  know  where  to  fix  his  pipes  when 
an  injection  is  to  be  accomplished,  whether  arterial 
or  venous,  or  both.  It  is  therefore  unnecessary  to 
extend  this  paper  by  describing  the  method  of  pro- 
ceeding in  each  individual  preparation,  general  rules 
being  suflBlcient,  and  to  the  intellectual  mind  much 
more  acceptable. 

DRIED  PREPARATIONS. 

Whenever  a section  of  the  body,  as  the  head,  the 
arm,  leg,  or  any  other  part,  is  to  be  injected,  the  arte- 
rial pipe  must  be  fixed  into  its  principal  trunk  or 
trunks : and  the  venous  pipe  into  one  of  the  extreme 
branches.  A very  common,  and,  indeed,  the  most 
frequent  source  of  misfortune  to  the  young  anatomist, 
is  the  neglecting  to  take  up  such  vessels  as  were  cut 
in  the  separation  of  the  part.  It  may  be  avoided  by 
blowing  into  the  pipes  when  fixed,  whereby  all  the 
ramifications  being  inflated,  such  as  are  cut  can  be  thus 
easily  found  out  and  secured. 

Male  subjects,  from  birth  till  the  age  of  twenty-five 
or  thirty,  answer  best  for  dried  preparations  of  the 


XXIV 


INTRODUCTION. 


■ greater  part  of  the  arterial  system.  After  thirty,  few 
subjects  answer  well  in  consequence  of  a profusion 
of  adeps  blending  itself  with  the  muscles,  and  not  un- 
frequently  of  a diseased  state  of  the  arterial  system. 

In  dried  preparations  the  arteries  should  be  fairly 
traced  in  all  their  ramifications,  and  the  muscles  sepa- 
rated from  each  other.  Every  thing  not  essential 
to  the  object  of  the  preparation  must  be  cut  away. 
When  the  part  is  fully  dissected,  care  should  be  taken  to 
put  every  portion  of  it  in  a proper  posture,  and  to  fix 
it  so  till  it  becomes  stiff  by  exposure  to  the  air.  The 
muscles  are  to  be  kept  asunder  by  strips  of  wood. 

When  the  preparation  is  thoroughly  dried,  and  not 
before,  it  should  be  varnished.  But  previously  to 
the  latter  process,  it  should  be  washed  twice  with 
a solution  of  caustic  potash,  in  order  to  remove  a 
greasy  coat  which  it  is  apt  to  form  on  its  surface.  It 
should  afterwards  be  washed  with  water  to  remove  the 
soap  that  results  from  the  application  of  the  potash. 
Soap-boiler’s  ley  answers  perfectly,  in  the  place  of  the 
caustic  potash  of  the  shops.  Dried  preparations  suf- 
fer much  from  insects,  and  the  best  security  for  them 
is  obtained  by  immersion  in  a solution  of  corrosive 
sublimate,  till  they  become  impregnated  with  it;  they 
may  afterwards  be  put  in  position  and  dried.  If  they 
are  too  large  to  subject  to  this  process,  even  after  they 


INTRODUCTION. 


XXV 


are  dried,  they  may  be  washed  four  times  advan- 
tageously with  this  mixture. 

Corrosive  Sublimate  ^i- 

Muriate  of  Ammonia,  Jiss. 

Water,  ifci. 

At  the  two  last  washings  add  to  the  foregoing 
Common  Glue,  dissolved,  ^i. 

The  glue  makes  the  mixture  adhere  to  the  prepara- 
tion, and' also  furnishes  for  the  varnish  a basis  or  ground, 
which  makes  it  stick  and  dry  well.  Two  thin  coats 
of  copal  varnish  must  afterwards  be  laid  on  with  a soft 
brush. 

CORRODED  PREPARATIONS. 

The  heart,  lungs,  liver,  spleen,  pancreas,  kidneys, 
and  penis,  are  most  commonly  chosen  in  making  corrod- 
ed preparations.  Their  vessels,  excretory  ducts,  and 
cavities,  as  the  case  may  be,  should  be  distended  mo- 
derately with  No.  I.  observing  to  give  to  each  system 
in  the  structure  of  the  viscus  a colour  different  from 
the  rest.  The  successful  injection  of  these  requires 
good  management,  because,  if  too  much  force  be  used, 
extravasation  will  occur  and  the  preparation  will  be 
materially  disfigure^. 


INTRODUCTION. 


xxvi 

After  injecting  it;,  the  preparation  is  to  be  laid  in  a 
mixture  of  three  parts  of  muriatic  acid;  with  one  of 
water,  which  corrodes  the  fleshy  part  and  leaves  the 
injection  exposed.  The  process  of  corrosion  occupies 
from  three  weeks  to  two  months,  according  to  the  bulk 
of  the  viscus.  The  acid  becomes  weakened  during  the 
time,  and  we  should,  therefore,  every  week,  add 
enough  of  the  fresh,  to  bring  it  to  its  original  strength. 

When  the  fleshy  part  is  converted  in  a soft  pulp,  the 
preparation  must  be  taken  out  of  the  mixture  with  the 
greatest  care  and  subjected  to  a small  gentle  stream 
of  water,  which  washes  off  the  pulp  and  leaves  the 
vessels  bare.  If  the  corroding  process  be  unfinished, 
the  part  must  be  replaced  in  the  acid  mixture  and 
kept  there  till  it  is  completed.  On  the  pulp  being 
removed,  let  the  preparation  remain  floating  in  water 
for  twenty  hours  in  order  to  remove  any  acid  which 
may  adhere  to  it;  then  dry  it  by  suspension  in  the  air 
or  by  laying  it  on  a heap  of  soft  carded  cotton,  covered 
with  a thin  cambrick  cloth,  in  order  to  prevent  the 
cotton  from  sticking  to  its  vessels. 

• 

As  corroded  preparations  break  from  the  slightest 
violence,  I have  latterly  used  with  great  improvement  to 
their  strength,  a size  of  isinglass,  into  which  they  were 
dipped;  by  repeated  applications  of  this  they  become 
well  coated  with  it,  and  thereby  too  strong  to  be  in- 
jured by  slight  jars. 


INTRODUCTION. 


XXVU 


The  preparation  should  be  fixed  on  a plaster  of  , 
Paris  pedestal,  and  varnished  by  dipping  it  into  copal 
varnish  diluted  with  one-half  its  quantity  of  spirits  of 
turpentine.  It  should,  after  drying,  be  varnished  in 
the  same  way  once  more.  Such  preparations,  when 
kept  under  glass  bells  or  cases,  are  among  the  most 
beautiful  that  can  be  made. 

WET  PREPARATIONS. 

Minute  injections  generally,  and  all  morbid  derange- 
ments, are  proper  subjects  for  wet  preparations.  The 
natural  structure  of  many  parts  is  also  very  advan- 
tageously displayed  in  this  way.  The  article  previ- 
ously to  being  put  up,  should  be  steeped  in  water, 
changed  daily,  till  all  the  blood  is  out. 

Spirits  of  wine,  spirits  of  turpentine,  and  a solution 
of  corrosive  sublimate,  are  each  excellent  for  suspend- 
ing such  preparations  in.  The  latter  answers  parti- 
cularly well  for  eyes  and  for  thin  membranous  parts, 
as  an  intestinej  &c.  Two  grains  of  corrosive  subli- 
mate, with  an  equal  quantity  of  muriate  of  ammonia, 
to  an  ounce  of  water,  make  a solution  sufficiently  anti- 
putrescent for  an  eye,  and  which  contracts  the  pre- 
paration much  less  than  spirits  of  wine.  When  larger 
bodies  are  preserved  the  quantity  of  corrosive  subli- 
mate must  be  increased  proportionately. 


xxviii  INTRODUCTION. 

Bottles  for  wet  preparations  should  have  wide 
mouths,  short  necks,  and  broad  heavy  bottoms.  The 
preparation  being  properly  displayed  and  suspended, 
the  mouth  of  the  bottle  must  be  secured  with  a blad- 
der; over  this  must  be  placed  sheet  lead,  about  the 
thickness  of  a quarter  of  a dollar,  and  trimmed  so 
as  to  correspond  in  size  with  the  top  of  the  bottle ; 
over  this  lead,  another  piece  of  bladder  is  to  be 
stretched  and  secured.  The  outside  bladder,  being 
properly  trimmed,  should  be  varnished  twice  with 
copal  varnish  coloured  with  lampblack. 

QUICKSILVER  INJECTIOKS. 

These  constitute  a beautiful  and  interesting  depart 
ment  in  the  occupations  of  the  practical  anatomist. 
The  parts  most  frequently  subjected  to  this  process 
are  the  lymphatics  and  lacteals.  In  the  extremi- 
ties we  introduce  the  tube  at  the  point  farthest  from 
the  heart,  and  having  injected  one  trunk,  the  pipe 
must  be  withdrawn  and  introduced  into  another,  and 
so  on  till  all  the  trunks  are  filled.  In  injecting  for  the 
lacteals  we  must  introduce  the  pipe  into  a lacteal  trunk 
in  the  mesentery  and  inject  backwards;  as  the  lacteals 
are,  on  the  intestine  itself,  for  the  most  part,  too 
small  to  admit  of  its  introduction  into  them. 

The  Liver  has  a great  many  lymphatics  in  its  peri- 
toneal coat;  the^  may  be  injected  from  one  of  the 


INTRODUCTION. 


XXIX 


trunks  on  the  broad  ligament.  It  is  unnecessary  to 
preserve  the  whole  liver ; a section  of  it  half  an  inch 
thick,  dried  and  hung  in  spirits  of  turpentine  answers 
very  well. 

The  Parotid  Gland  injected  with  quicksilver,  from 
its  duct,  affords  a fine  preparation.  The  injection  must 
be  made  before  the  gland  is  removed  from  the  body ; 
the  blood  should  afterwards  be  soaked  out,  and  the 
gland  dried  and  hung  in  spirits  of  turpentine. 

The  VesiculsB  Seminales  and  the  Testicles  of  the 
adult,  are  also  excellent  subjects  for  this  kind  of  prepa- 
ration. The  lactiferous  ducts  of  the  mammse  are  very . 
favourably  displayed  in  the  same  manner ; they  are 
injected  separately  from  the  nipple.^  A woman  who 
has  died  during  lactation  is  the  best  subject  for  it. 

The  hand  of  a thin,  aged  female  may  be  readily  in- 
jected, both  arteries  and  veins,  by  a pipe  fixed  into 
the  radial  artery.  After  it  is  filled  it  should  be  mace- 
rated in  water  frequently  changed,  till  all  the  blood  is 
removed  and  the  cuticle  comes  off;  it  should  then  be 
dried  and  varnished. 

* Bristles  should  be  previously  introduced  into  each  duct, 
and  ■withdrawn  successively  as  the  injection  advances,  other- 
wise we  may  commit  the  mistake  of  injecting  a duct  twice.  As 
each  duct  is  injected,  it  should  be  secui-ed  with  a ligature. 


XXX 


l^^TRODUCTION. 


The  Veins  of  the  kidney  of  a cat  are  said  to  afford  a 
beautiful  preparation  with  quicksilver. 

PREPARING  BONES. 

Bones  are  best  prepared  by  maceration  in  warm 
weather,  and  a dropsical  subject  is  much  better  than 
any  other,  from  the  marrow  being  less  abundant  and 
mixed  with  serum.  The  skeleton  should  be  roughly 
cleaned  and  put  into  a macerating  vessel,  the  brain 
being  removed.  The  water  should  be  changed  daily 
as  long  as  it  is  discoloured  by  the  blood.  Afterwards 
it  should  be  left  till  putrefaction  has  softened  and  dis- 
solved all  the  ligaments  and  soft  parts.  The  skeleton 
should  then  be  taken  out  and  washed  well  in  clean 
water  with  a little  ley  added  to  it.  It  is  then  to  be 
dried  and  is  fit  for  use.  If  the  maceration  be  pro- 
perly conducted  no  bleaching  is  necessary ; if  other- 
wise, the  process  adopted  in  whitening  linen  and  cot- 
ton clothing  answers  well,  that  is,  exposure  to  the  sun. 
frequent  wetting  with  water,  and  chlorine. 

A cranium  from  four  to  ten  years  old  treated  in  tliis 
way  affords  a fine  preparation  for  studying  its  bones 
in  a state  of  separation.  To  accomplish  the  latter  it 
is  only  necessary  to  fill  its  cavity  mth  peas  or  beans 
after  the  maceration  is  over,  and  to  immerse  it  in  warm 
water.  The  beans  in  a short  time  begin  to  swell  and 


INTRODUCTION. 


XXXI 


open  the  sutures  completely.  The  bones  of  the  face 
must  be  taken  asunder  with  the  fingers. 

In  order  to  show  the  animal  part  only  of  bone,  take 
a section  of  it  and  immerse  it  in  an  acid  mixture  com- 
posed of  muriatic  acid  one  ounce,  and  water  one  quart. 
In  from  one  to  four  months,  according  to  the  size  and 
solidity  of  the  bone,  the  calcareous  part  will  be  taken 
away  by  the  acid.  On  such  a preparation  one  may 
demonstrate  the  pliability  and  the  lamellated  and 
fibrous  texture  of  the  hardest  bone. 

A bone,  by  being  thrown  into  a strong  fire,  will 
have  all  its  animal  part  destroyed  and.  nothing  but  the 
calcareous  left.  This  preparation  is  the  reverse  of 
the  last. 

To  demonstrate  the  vascularity  of  bone,  cut  off  the 
limb  of  a foetus,  or  of  a young  child,  and  fix  a pipe  into 
the  principal  artery.  By  filling  the  part  with  the 
size  injection,  the  vessels  of  the  bone  will  also  be 
injected.  Remove  the  flesh  when  it  becomes  cold, 
and  macerate  in  water  till  the  blood  is  washed  out. 
Place  the  bone  in  the  acid  mixture  just  mentioned  till 
the  calcareous  part  is  removed  j soak  it  in  pure  water 
again  for  a day,  then  dry  it,  and  finally  immerse  it  in 
spirits  of  turpentine  to  make  it  transparent. 


INTRODUCTION. 


xxxii 

ON  FUMIGATION. 

The  air  of  rooms  where  dead  bodies  are  kept,  as 
well  as  the  walls  and  furniture,  become  exceedingly 
offensive;  to  correct  which  we  resort  to  the  following 
mixture  with  great  advantage. 


Take  Black  Oxyd  of  Manganese,  ji. 

Comnaon  Salt, 

Sulphuric  Acid, 

Water, 

The  water  and  the  acid  should  be  previously  mixed 
and  allowed  to  cool.  Then  stir  all  the  ingredients  well 
together  in  a stone  vessel. 

When  the  room  is  abandoned  for  the  night,  close 
its  doors  and  windows  and  commence  this  fumigation. 
The  next  morning  it  will  be  found  much  sweetened, 
and  on  ventilating  freely  its  atmosphere  will  loose  still 
more  of  its  offensiveness  and  be  in  a great  measure 
renovated. 

The  fumes  of  this  mixture  are  very  penetrating; 
they  give  their  peculiar  smell  to  clothing  for  several 


^ . • 
3y- 

5vi. 

5iss. 


INTRODUCTION. 


XXXlll 


days,  and  rust  metallic  surfaces  intensely.  All  articles, 
therefore,  which  are  not  intended  for  such  depuration 
should  be  removed. 


Students  of  Anatomy,  have  their  fears  much  excited  on  the 
score  of  the  constitutional  symptoms,  arising  from  small  wounds 
inflicted  during  their  dissections ; under  an  erroneous  impression, 
that  a specific  virus  is,  thereby,  introduced  into  the  system. 
Inconveniences  of  this  kind,  though  they  do  occasionally  occur, 
are  by  no  means  frequent;  and  are  just  as  apt  to  be  produced 
from  the  prick  of  a needle,  of  a brier,  or  of  an  oyster-shell.  The 
first  intimation  of  such  mischief,  is  the  part  becoming  painful, 
red,  and  swollen,  and  the  arm  getting  somewhat  stiff;  if  in  the 
eai-ly  stage  of  these  symptoms,  a blister  be  applied  according  to 
the  recommendation  of  Dr.  Physick,  the  person  live  light,  and 
take  a saline  cathaidic,  the  treatment  is  almost  invariably  suf- 
ficient for-the  cure.  Such  accidents  are  much  more  liable  to 
occur  from  the  prick  of  a spicula  of  bone,  than  from  any  other 
cause  to  which  the  Anatomist  is  exposed,  furnishing  thereby, 
a useful  hint  for  him,  never  to  break  a bone,  but  always  to  saw  it 
oft'  smoothly. 


c 


LESSONS 


IN 

PRACTICAL  ANATOMY. 


PART  I. 

OF  THE  HEAD  AND  NECK. 


CHAPTER  I. 

Of  the  External  Parts  of  the  Head  and  JVeck. 

The  integuments  of  the  head  are  rem&rkably  thick 
and  hard,  but  give  the  sensation,  when  felt  externally, 
of  being  a very  thin  layer  spread  over  the  hones.  The 
latter  is  particularly  the  case  as  far  as  the  hair  extends. 
They  consist  of  skin,  and  below  it  of  small,  compact, 
granulated  masses  of  fat  enclosed  in  the  cells  of  a cellu- 
lar substance,  which  has  very  much  of  a ligamentous 
character,  and  adheres  closely  to  the  muscle  and  ten- 
dinous matter  beneath. 

The  muscles  of  the  face  should  always  be  dissected 
as  early  as  possible  after  death;  under  the  most  favour- 
able circumstances  they  are  difficult  for  the  student  to 
make  out,  and  are  rendered  unintelligible  to  him  in  a 

A 


OF  THE  HEAD  AND  NECK. 


2 

few  days  by  the  changes  which  their  diminution  of 
volume,  infiltration,  and  confusion  of  colour  with  con- 
tiguous parts,  produce. 

I would  also  advise  one  side  of  the  face  and  neck  to 
be  appropriated  exclusively  to  the  dissection  of  the 
fasciae,  muscles,  and  glands;  every  thing,  therefore, 
should  be  removed  which  interferes  with  a thorough 
examination  of  them.  The  student  having  accomplish- 
ed this,  may  afterwards  work  on  the  other  side  of  the 
subject  for  the  blood-vessels  and  nerves.  To  trace  the 
arteries  properly,  they  ought  to  be  filled  previously 
with  common  injection;  tallow,  coloured  with  red  lead, 
answers  very  well ; it  is  of  less  importance  to  inject  the 
veins.  It  is  unnecessary  to  heat  the  subject  for  such 
injection. 


Section  I. 

Of  the  Muscles  and  Fasciae. 

The  OcciPiTO-FRONTALis  muscle  consists  of  tw’o 
symmetrical  parts,  and  coming  from  the  back  of  the 
head  is  inserted  into  the  front  of  it;  it  has  four  bellies 
of  muscular  fibres,  two  behind  and  twm  before,  con- 
nected by  a thin  tendon  which  covers  all  the  top  of  the 
head.  The  dissection  of  this  muscle  is  difficult,  from 
the  close  adhesion  of  its  tendon  to  the  pericraniiun  be- 


MUSCLES  AND  FASCIA. 


3 


lowj  and  to  the  integuments  of  the  head  above.  It 
is  best,  therefore,  to  commence  by  making  one  incision, 
through  the  integuments  only,  fi’om  the  root  of  the  nose 
to  the  fore  end  of  the  sagittal  suture,  and  another  from 
the  commencement  of  the  first  along  the  upper  margin 
of  the  eyebrows  to  the  external  angular  process  of  the 
os  fronds ; by  raising  up  this  flap  it  leads  to  the  dissec- 
tion of  the  whole  muscle. 

It  arises  from  the  superior  transverse  ridge  of  the  os 
occipitis  by  tendinous  and  fleshy  fibres,  which  form  two 
distinct  bellies  about  an  inch  and  a half  long,  one  on 
each  side  of  the  bone.  Its  tendon,  when  carefully 
traced,  will  be  found  terminating  a little  in  front  of  the 
coronal  suture  in  the  two  anterior  fleshy  bellies  which 
cover  the  whole  front  part  of  the  os  fronds.  The  in- 
ternal edges  of  these  latter  are  in  conjimcdon  below. 

It  is  inserted  fleshy,  on  each  sjde,  into  the  superior 
margin  of  the  orbicularis  ocuii  and  corrugator  super- 
cilii,  and  by  its  nasal  slip  into  the  internal  angular  pro- 
cess of  the  os  fronds  and  into  the  root  of  the  os  nasi. 

It  pulls  the  skin  of  the  head  backw’ards  and  for- 
wards, and  throws  the  forehead  into  horizontal  wrin- 
kles. It  also  elevates  the  supercilia. 

The  Compressor  Naris  arises  by  a pointed  begin- 
ning from  the  root  of  the  ala  nasi ; it  spreads  like  a fan 
over  the  lateral  parts  of  the  nose  below,  is  inserted  into 
its  fellow  of  the  opposite  side,  on  the  dorsum  of  the 
nose,  and  into  the  lower  part  of  the  os  nasi,  where  it  is 
connected  with  the  nasal  slip  of  the  occipito  frontalis. 


4 


OF  THE  HEAD  AND  NECK. 


This  muscle  consists  of  thin  and  pale  fibres  imme- 
diately under  the  skin.  If  it  act  from  both  extremi- 
ties, by  its  curved  fibres  being  made  straight,  it  will 
compress  the  nostril ; but  if  it  act  from  its  dorsal  mar- 
gin assisted  by  the  nasal  slip  of  the  occipito  frontalis,  it 
will  dilate  the  ala  nasi,  and  has,  therefore,  been  called 
dilatans  nasum  by  Columbus. 

The  Orbicularis  Palpebrarum  is  a broad  circu- 
lar muscle,  lying  immediately  under  the  skin  of  the 
eyelids,  and  over  the  tarsi  cartilages.  It  covers  the 
whole  front  of  the  bony  orbit  and  extends  from  four  to 
eight  lines  beyond  its  margin,  being  connected  to  sub- 
jacent parts  by  cellular  tissue ; its  temporal  section  is 
fastened  to  the  temporal  fascia  beneath. 

It  arises  fleshy  from  the  internal  angular  process  of 
the  frontal  bone  and  from  the  upper  edge  of  the  round 
hoinzoutal  tendon  that  fixes  the  internal  commissure  of 
the  eyelids  to  the  nasal  process  of  the  superior  maxilla. 
These  fibres  perform  the  circuit  of  the  eyelids,  and, 
coming  around  to  the  internal  canthus  again,  are  insert- 
ed into  the  orbitar  margin  of  the  nasal  process,  and  of 
the  orbitar  process  of  the  upper  maxilla,  into  the  lower 
edge  of  the  horizontal  tendon,  and  into  tlie  nasal  pro- 
cess just  beneath  it. 

The  Ciliaris  muscle  is  the  internal  mai-gin  of  the 
orbicularis  planted  on  the  edges  of  the  tai’si  cartilages. 

As  the  Orbicularis  muscle  is  fixed  at  its  nasal  and 
temporal  sections  more  than  elsewhere,  it  is  obvious 


MUSCLES  AND  FASCIA. 


o 


that  the  contraction  of  its  circular  or  curved  fibres  by 
making  them  straight,  mil  close  the  eyelids  and  wrinkle 
the  skin  on  them.  This  muscle  frequently  has  a slip 
fi’om  its  lower  border  to  the  upper  lip,  anterior  to  the 
2ygomaticus  minor. 

The  CoRRUGATOR  SuPERCiLii  is  placed  at  the  in- 
ternal end  of  the  superciliary  ridge.  It  arises  from  the 
internal  angular  process  of  the  os  frontis,  and  passing 
obliquely  upwards  and  outwards  between  the  lower 
edge  of  the  occipito  frontalis  and  the  upper  edge  of 
the  orbicularis,  is  concealed  by  them.  It  is  inserted 
into  the  former  principally,  but  its  fibres  also  blend 
with  the  latter. 

It  draws  the  forehead  into  vertical  wrinkles. 

The  Levator  Labii  Superioris  Aljeque  Nasi  is 
fixed  just  at  the  side  of  the  nose.  It  arises  by  a point- 
ed production  from  the  nasal  process  of  the  superior 
maxilla  at  the  external  canthus  of  the  eye,  and  by  a 
broad  origin  from  the  anterior  margin  of  the  orbitar 
process  of  the  same  bone.  Passing  downwards  it  is 
inserted  into  the  side  of  the  ala  nasi,  and  into  the  up- 
per lip,  being  narrower  below  than  above. 

It  draws  the  upper  lip  and  the  ala  nasi  upwards. 

The  Levator  Anguli  Oris  is  a small  muscle  con- 
cealed very  much  by  the  last;  it  arises  from  the  ante- 
rior part  of  the  superior  maxillary  bone,  between  the 


6 


OF  THE  HEAD  AND  NECK. 


foramen  infra-orbitarium  and  the  first  small  grinder,  and 
is  inserted  into  the  corner  of  the  mouth. 

It  raises  up  the  angle  of  the  mouth. 

The  Zygomaticus  Minor  is  a small  muscle  some- 
times deficient,  arising  from  the  fore  part  of  the  os 
malse  5 it  descends  obliquely  and  is  inserted  into  the 
upper  lip  just  above  the  corner  of  the  mouth. 

The  Zygomaticus  Major,  being  just  on  the  out- 
side of  the  last  and  much  larger,  aiises  from  the  malar 
bone  externally,  at  its  posterior  inferior  part  just  above 
the  lower  edge,  where  this  bone  contributes  to  form 
the  zygoma,  and  passing  obliquely  downwards  it  is  in- 
serted into  the  corner  of  the  mouth,  by  running  into  the 
depressor  anguli  oris. 

These  two  last  muscles  di-aw  the  corner  of  the  mouth 
towards  the  cheek  bone,  or  obliquely  upwards  and  Out- 
wards as  in  smiling. 

The  Depressor  Labii  Superioris  Aljeque  Nasi 
is  concealed  by  the  orbicularis  oris  and  by  the  levator 
labii  superioris  alseque  nasi.  To  get  a view  of  it  the 
upper  lip  must  be  inverted  and  the  lining  membrane 
of  the  mouth  removed  on  the  side  of  the  frsenum  of  the 
lip.  This  muscle  arises  from  the  inferior  part  of  the 
upper  maxilla  in  front  of  the  alveolar  processes  for  the 
dens  caninus  and  the  incisores,  and  is  inserted  into  the 


MUSCLES  AND  FASCIA. 


/ 

side  of  the  ala  nasi  and  into  the  contiguous  part  of  the 
upper  lip. 

It  depresses  the  upper  lip  and  the  ala  nasi'. 

The  Depressor  Anguli  Oris  arises  broad  and 
fleshy  from  the  base  of  the  lower  jaw  on  the  side  of  the 
chin ; being  somewhat  triangular,  its  apex  is  inserted 
into  the  corner  of  the  mouth.  ’ 

This  muscle  draws  the  corner  of  the  mouth  down- 
~ wards.  It  lies  immediately  under  the  skin,  and  blends 
above  with  the  zygomaticus  major  and  with  tlie  leva- 
tor anguli  oris. 

The  Depressor  Labii  Ixferiorts  is  in  part  be- 
neath the  last  muscle,  and,  like  it,  arises  broad  and 
fleshy  from  the  basis  of  the  lower  jaw  on  the  side  of 
the  chin ; its  fibres  pass  obliquely  upwards  and  inwards 
and  are  inserted  into  the  whole  side  of  the  lower- lip. 

It  draws  the  lip  downwards. 

These  two  last  muscles  are  much  obscured  by  being 
mixed  with  a quantity mf  adipose  matter ; the  skin,  also 
is  closely  blended  with  them,  and  the  roots  of  the  beard 
penetrate  between  the  intervals  of  their  fibres. 

The  Levator  Labii  Inferioris,  being  placed  be- 
neath the  depressor  labii  inferioris,  is  demonstrated  by 
turning  downwards  the  lower  lip  and  dissecting  away 
its  lining  membrane  on  the  side  of  the  frmnum ; it  will 
then  be  seen  to  arise  in  front  of  the  alveolar  process  of 


OF  THE  HEAD  AND  NECK. 


the  external  incisor  and  the  canine  tooth,  and  pass- 
ing obliquely  downwards  to  be  inserted  into  the  lower 
lip. 

It  elevates  the  lower  lip. 

The  Buccinatoe  muscle  arises  from  the  root  of  the 
coronoid  process  of  the  lower  jaw  bone,  from  the  back 
part  of  the  upper  maxilla  near  the  pterygoid  process 
and  from  the  roots  of  the  alveolar  processes  of  both 
bones  as  far  forwards  as  the  dentes  bicuspides.  It  is  in- 
serted into  the  corner  of  the  mouth  and  into  the  con- 
tiguous parts  of  the  upper  and  lower  lip. 

It  draws  the  corners  of  the  mouth  directly  back- 
wards. 

The  Orbicularis  Oris  is  a circular  muscle  just 
beneath  the  skin,  much  blended  with  adipose  matter 
externally,  but  more  plain  on  the  surface  contiguous  to 
the  lining  membrane  of  the  mouth.  It  constitutes  a 
considerable  part  of  the  thickness  of  the  lips,  and  sur- 
round the  mouth  entirely.  It  has  no  bony  origin,  but 
arises  from  the  fibres  of  the  several  muscles  which  join 
each  other  at  the  corner  of  the  mouth,  and,  therefore, 
consists  of  two  semicircular  planes,  one  for  the  upper, 
and  the  other  for  the  lower  lip. 

It  is  the  antagonist  to  most  of  the  other  muscles  of 
the  mouth.  From  its  superior  part  a pyramidal  slip 
goes  to  the  tip  of  the  nose,  called  by  Albinus,  Nasalis 
Labii  Superioris. 


MUSCLES  AND  FASCIA. 


9 


The  Masseter  is  placed  immediately  under  the 
skin,  and  forms  the  fleshy  protuberance  on  the  back  of 
the  face  before  the  ear.  It  arises  tendinous  and  fleshy 
from  the  malar  process  of  the  upper  maxilla,  and  from 
the  inferior  edge  of  the  malar  bone  between  the  maxil- 
lary and  zygomatic  sutures;  it  arises  also  from  the 
temporal  bone  between  the  zygomatic  suture  and  the 
tubercle.  The  masseter  covers  all  the  exterior  surface 
of  the  ramus  of  the  lower  jaw,  as  low  down  as  its  base. 
It  is  divided  into  two  portions,  which  lie  one  beneath 
the  other;  the  internal  is  the  smaller,  and  is  inserted 
tendinous  into  the  outer  part  of  the  root  of  the  coronoid 
process.  The  external  extends  from  the  malar  bone  to 
the  angle  of  the  inferior  maxilla,  where  it  is  inserted 
tendinous  and  fleshy.  A part  of  the  internal  portion 
may  be  seen  at  the  zygomatic  suture  behind  the  exter- 
nal, without  the  latter  being  raised  up. 

It  closes  the  jaws. 

The  Temporalis  lies  on  the  side  of  the  head  occupy- 
ing its  middle  inferior  region ; it  is  covered  externally 
by  a thick ' dense  tendinous  membrane,  the  fascia  tem- 
poralis, which  arises  from  the  semicircular  ridge  on  the 
side  of  the  cranium,  and  is  inserted  into  the  upper  mar- 
gin of  the  zygoma.  By  removing  this  fascia,  the  tem- 
poral muscle  is  seen  to  arise  fleshy  from  its  inner  sur- 
face, from  the  semicircular  ridge  on  the  side  of  the  os 
ffontis  and  parietale  its  whole  length,  also  from  the  sur- 
faces of  bone,  between  this  ridge  and  the  zygoma  in- 

B 


10 


OF  THE  HEAD  AND  NECK. 


eluding  a part  of  the  frontal  bone,  the  lower  part  of  the 
parietal,  and  the  squamous  portion  of  the  temporal. 
From  this  extensive  origin,  the  fibres  converge  to* 
wards  the  zygoma  and  are  inserted  tendinous  into  the 
coronoid  process  of  the  lower  jaw,  surrounding  it  on 
every  side ; some  of  these  tendinous  fibres  in  front  go 
down  nearly  as  low  as  the  last  dens  molaris. 

The  temporalis  receives  a small  accession  of  fleshy 
fibres  from  the  internal  face  of  the  zygoma.  It  pulls 
the  lower  jaw  directly  upwards. 

Of  the  Muscles  of  the  A^eck.  The  dissection  of  this 
part  can  now  be  advantageously  pursued;  with  this 
view,  make  one  incision  through  the  skin,  along  the 
clavicle  and  upper  edge  of  the  sternum,  another  from 
the  chin,  over  the  thyroid  cartilage  to  the  sternum, 
and  a third  from  the  chin  to  the  upper  part  of  the  ear. 

The  flap  which  is  thus  marked  out  it  to  be  raised 
carefully  without  cutting  up  a superficial  membrane 
that  lies  immediately  below  the  skin  called  Fascia  Su- 
perficialis.  This  fascia  is  a continuation  of  the  one 
placed  in  front  of  the  abdominal  muscles,  which  passes 
from  them  to  the  thorax  and  afterwards  to  the  neck. 
Its  connexion  with  the  clavicle  and  sternum  is  not  very 
strong,  and  it  goes  from  them  along  the  neck  to  the 
face,  being  slightly  fastened  to  the  base  of  tlie  lower 
jaw  in  advance  of  the  masseter  muscle.  It  is  spread 
over  the  parotid  gland,  is  fixed  to  tlie  mastoid  process, 
to  the  meatus  auditorius,  and  to  Uie  zygoma : in  the  lat- 


MUSCLES  AND  FASCIA. 


11 


ter  place  it  is  continuous  in  some  measure  with  the  fas- 
cia temporalis.  The  existence  of  this  membrane  is 
thought,  by  Mr.  Colles  of  Dublin,  to  obscure  very  much 
the  affections  of  the  neck  and  of  the  parotid  gland, 
checking  the  development  of  tumours,  rendering  their 
fluctuation  and  particular  feel  very  equivocal,  and  giv- 
ing a wrong  course  to  their  pus  when  they  suppurate. 
The  fascia  superficialis  is  better  marked  over  the  paro- 
tid gland,  and  about  the  base  of  the  jaw,  than  lower 
dow. 

The  Platysma  Myoides  muscle,  or  the  Musculus 
CuTANEUS,  is  immediately  beneath  the  fascia  superfi- 
cialis ; covers  a very  considerable  portion  of  the  side 
of  the  neck ; and  extends  from  the  thorax  obliquely  to 
the  face. 

It  arises  from  the  condensed  cellular  membrane  on 
the  upper  part  of  the  pectoralis  major  muscle  and  the 
deltoid,  just  below  the  clavicle  and  nearly  the  whole 
length  of  this  bone.  Its  fibres  are  much  more  pale 
than  those  of  other  muscles,  are  collected  into  longitu- 
dinal fasciculi,  constituting  a plane  of  scarcely  a line  in 
thickness,  and  terminate  in  the  integuments  of  the  lower 
jaw  and  cheek.  It  is  slightly  attached  to  the  lower  jaw, 
and  sometimes  has  the  appearance  of  running  into  the 
muscles  of  the  lower  part  of  the  face. 

When  the  whole  muscle  is  in  action  it  elevates  the 
skin  of  the  neck.  The  external  jugular  vein  is  seen 
running  nearly  in  the.  centre  of  it  in  the  same  direction 


12 


OF  THE  HEAD  AND  NECK 


with  the  fibres  of  this  muscle  between  it  and  the  sterno- 
mastoid. 

The,  Sterno-Cleido-Mastoideus  is  beneath  and 
decussates  the  last  muscle.  It  forms  always  a promi- . 
nent  feature  in  the  outline  of  the  neck,  passing  obli- 
quely from  the  upper  front  part  of  the  thorax  to  the 
bas(Tof  the  cranium. 

It  arises  tendinous  and  fleshy  from  the  edge  of  the 
upper  part  of  the  sternum,  and  fleshy  from  the  ster- 
nal end  of  the  clavicle.  These  origins  are  separated  by 
a considerable  fissure ; they  soon  unite  and  are  insert- 
ed tendinous  into  the  mastoid  process  and  into  part  of 
the  transverse  ridge  of  the  occipital  bone  next  to  it. 

It  draws  the  chin  towards  the  sternum.  This  mus- 
cle is  to  be  detached  from  its  origin,  and  allowed  to 
hang  aside  by  its  insertion,  in  order  to  get  at  the  parts 
beneath.  We  shall  then  see  two  narrow,  handsome 
ribbon-like  muscles  on  each  side  of  the  middle  line  of 
the  trachea;  they  are  the  sterno-hyoideus  and  sterno- 
thyroideus.  But  before  we  go  to  the  dissection  of 
them,  it  is  necessary  to  look  at  another  fascia  of  the 
neck. 

When  the  origin  of  the  sterno-cleido-mastoideus  is 
turned  to  one  side,  beneath  the  fascia  superficialis  and 
somewhat  separated  from  it  by  a lamina  of  cellular 
adipose  matter,  is  seen  the  Fascia  Profunda  of  the 
neck.  This  membrane  arises  from  the  larynx,  forms  a 
thin  capsule  to  the  thyroid  gland,  and,  being  closely 


MUSCLES  AND  FASCIA. 


13 


attached  to  its  inferior  margin,  it  descends  by  invest-' 
ing  the  sterno- hyoid  and  thyroid  muscles,  being  strong 
and  well  marked  on  their  anterior  surfaces.  It  is  firm- 
ly fastened  to  the  upper  edge  of  the  sternum,  the  ster- 
« nal  end  of  the  cla\dcle,  and  to  the  cartilages  of  the  first 
ribs,  forming  an  elastic  and  resisting  membrane  from 
the  larynx  to  the  thorax.  By  turning  off  the  sterno- 
hyoid and  thyroid  muscles  from  their  attachment  to 
the  sternum,  the  fascia  profunda  will  be  seen  still  more 
distinctly  passing  behind  them  from  the  inferior  mar- 
gin of  the  thyroid  gland  to  the  upper  bone  of  the  ster- 
num, this  lamina  of  it  being  inserted  into  the  sternum 
twelve  or  fifteen  lines  below  its  upper  edge.  It  en- 
closes or  surrounds  the  transverse  vein  and  the  arteria 
innominata.  Beneath  the  fascia  profunda,  are  the 
trachea,  the  roots  of  the  arteries  of  the  head  and  upper 
extremities,  and  the  trunks  of  their  veins.  There  is 
much  loose  cellular  and  adipose  matter  placed  at  the 
lower  part  of  the  neck  beneath  this  fascia,  between  it 
and  the  trachea,  through  which  the  thyroid  veins  with 
their  ramifications  pass.  This  last  circumstance  must 
always  render  suppurations  and  operations  in  the  part 
highly  dangerous,  as  the  pus  will  form  fistulsB  under 
the  sternum ; moreover,  the  continual  motion  of  the 
part  in  respiration  prevents  adhesion  from  occurring, 
and,  therefore,  disposes  to  ulceration.  An  ingenious 
idea  on  the  uses  of  this  fascia  and  of  the  sterno- hyoid 
and  thyroid  muscles  as  connected  with  it,  was  suggest- 
ed by  the  late  Allan  Burns  ; he  conceived  that  they 


14 


OF  THE  HEAD  AND  NECK. 


were  a defence  to  the  upper  part  of  the  thorax,  and 
sustained  the  atmospheric  pressure,  which,  without 
them,  would  fall  upon  the  trachea  and  produce  difficul- 
ty of  breathing,  from  the  air  not  passing  through  the 
larynx  sufficiently  rapidly  to  keep  pace  with  the  dila-  • 
tation  of  the  thorax.  He  illustrates  the  opinion  by  a 
case  very  much  in  point,  of  a gentleman  who  had  lost 
thirfascia  and  the  muscles  by  suppuration,  and  who  was 
afterwards  incommoded  by  atmospheric  pressure  upon 
the  trachea  at  this  point. ^ 

The  external  borders  of  the  fascia  profunda  are  con- 
tinued into  the  sheaths  of  the  gi’eat  vessels  of  the 
neck.  It  and  the  fascia  superficialis  are  also  continu- 
ous with  each  other  along  the  anterior  edge  of  the  ster- 
no-cleido-mastoideus. 

Within  the  inferior  maxilla,  at  its  angle,  a ligament- 
ous expansion  arises  from  the  pterygoideus  externus 
muscle,  and  is  spread  out  between  the  styloid  process 
and  the  ramus  of  the  lower  jaw.  This  membrane  is 
joined  by  the  fascia  superficialis  at  its  inferior  edge, 
just  before  the  upper  part  of  the  sterno-mastoideus, 
which  increases  its  breadth  downwards  in  the  neck,  giv- 
ing it  somewhat  the  condition  of  a vertical  septum  of 

Dr.  Lawrance  informs  me  that  this  fascia  profunda  is  v ell 
developed  in  the  neck  of  a cat,  and  that  having  occasion  to  re- 
move it  in  an  experiment;  the  respiration  of  the  animal  was 
conducted  with  great  difficulty,  amounting  almost  to  suffocation. 
This  is  a good  confirmation  of  Mr.  Burns’s  hypothesis. 


MUSCLES  AND  FASCIA.  15 

that  region,  and  at  its  lower  edge  it  runs  into  the  theca 
of  the  great  vessels  of  the  neck.  Through  its  lower 
part,  penetrate  the  stylo-hyoideus  and  digastricus  mus- 
cles, and  the  upper  part  separates  the  parotid  from 
the  submaxillary  gland.  It  is  felt  like  a cord  extend- 
ing downwards  and  backwards  below  the  angle  of  the 
maxilla  inferior.  It  is  connected  at  its  internal  edge 
with  the  compages  of  the  nerves  and  vessels  oT-the 
part  in  such  a manner  as  to  forbid  description,  but  the 
practical  anatomist  will  find  no  difficulty  in  discovering 
and  understanding  it. 

Below  this  septum  a round  ligament  like  a nerve 
passes  from  the  extremity  of  the  styloid  process  to  the 
appendix  of  the  os  hyoides. 

The  Sterno  Hyoideus  arises  thin  and  fleshy  on 
the  interior  of  the  thorax  from  the  approximated  sur- 
faces of  the  cartilage  of  the  first  rib,  the  clavicle,  and 
the  first  bone  of  the  sternum ; it  passes  upwards, some- 
what obliquely  and  is  inserted  into  the  inferior  edge 
of  the  base  of  the  os  hyoides. 

It  draws  the  os  hyoides  towards  the  sternum. 

The  Sterno  Thyroideus  is  beneath  the  last  and 
concealed  in  a considerable  degree  by  it.  It  arises 
fleshy  from  the  interior  surface  of  the  sternum,  about 
an  inch  below  its  upper  margin,  and  from  the  cartilage 
of  the  first  rib ; diminishing  in  breadth  somewhat  as  it 


16 


OF  THE  HEAD  AND  NECK. 


ascends,  it  is  inserted  obliquely  into  the  side  of  the  thy- 
roid cartilage 

It  draws  this  cartilage  towards  the  sternum. 

The  Thyreo  Hyoideus,  arises  obliquely  from  the  , 
side  of  the  thyroid  cartilage  externally,  and  is  inserted 
into  a part  of  the  base  and  nearly  all  the  cornu  of  the. 
os  hyoides.  It  looks  like  a continuation  of  the  last. 

Use ; To  draw  up  the  thyroid  cartilage. 

The  Omo  Hyoideus  passes  obliquely  across  the  neck 
from  the  superior  edge  of  the  scapula  to  the  os  hyoides. 
It  is  a thin  narrow  muscle  divided  into  two  bellies,  one 
at  each  end,  by  an  intermediate  tendon,  its  inferior  part 
is  concealed  by  the  trapezius  muscle,  its  middle,  where 
the  tendon  exists,  crosses  the  great  vessels  of  the  neck 
and  is  covered  by  the  sterno-cleido-mastoid  muscle, 
and  its  upper  extremity  is  over-lapped  by  the  platysma 
myoides. 

It  arises  from  the  scapula  just  behind  the  notch  in  its 
superior  costa,  and  curving  somewhat  downwards  in  its 
course  is  inserted  into  the  lower  edge  of  the  base  of  the 
os  hyoides  next  to  its  cornu. 

It  draws  the  os  hyoides  dowTiwards. 

The  Digastricus  is  a double-bellied  muscle  at  the 
upper  side  of  the  neck,  passing  from  tlie  back  pai’t  of 
the  base  of  the  head  to  the  chin.  It  arises  from  the 
fossa  of  the  temporal  bone  at  the  inside  of  the  mastoid 
process,  principally  fleshy ; as  the  muscle  descends  to- 


MUSCLES  AND  FACI^. 


17 


wards  the  os  hyoides,  a round  tendon  forms  its  middle 
part,  which  passes  through  the  stylo  hyoideus  muscle, 
and  is  fixed,  by  a ligamentous  loop,  to  the  cornu  of  the 
os  hyoides.  After  this  the  muscle  becomes  again  fleshy, 
and  is  inserted  into  the  inside  of  the  base  of  the  maxilla 
inferior  at  the  side  of  the  chin.  It  receives  an  acces- 
sion from  the  base  of  the  os  hyoides.  ^ 

It  draws  the  os  hyoides  upwards.  By  raising  the 
posterior  belly  of  this  muscle  we  get  a better  view  of 
the  styloids,  which  are  three  in  number,  and  placed 
within  it. 

The  StyloHyotdeus,  being  the  more  superficial  of 
the  three,  arises  tendinous  from  the  middle  and  inferior 
part  of  the  styloid  process  of  the  temporal  bone,  and 
being  perforated,  as  mentioned,  by  the  tendon  of  the 
digastricus,  is  inserted  tendinous  into  the  cartilaginous 
juncture  of  the  base  and  cornu  of  the  os  hyoides. 

It  draws  the  os  hyoides  upwards  and  backwards. 

The  Stylo  Glossus  is  within  and  above  the  other; 
it  arises  from  the  upper  internal  part  of  the  styloid 
process,  tendinous  and  fleshy,  and  is  inserted  into  the 
side  of  the  root  of  the  tongue  forming  thereby  a part  of 
its  structure. 

It  draws  the  tongue  backwards. 

The  Stylo  Pharyngeus  is  more  deeply  situated 
than  either  of  the  other  two  muscles.  It  arises  from  the 

c 


18 


OF  THE  HEAD  AND  NECK. 


inner  side  of  the  styloid  process  near  its  root,  and  is  in- 
serted into  the  side  of  the  pharynx  between  the  middle 
and  upper  constrictors,  opposite  the  tonsil  gland.  It 
afterwards  continues  between  the  lining  membrane  of 
the  pharynx  and  the  middle  and  lower  constrictors,  to 
the  posterior  margin  of  the  thyroid  cartilage. 

It  draws  the  larynx  and  pharynx  upwards. 

The  Mylo-Hyoideus  forms  the  floor  of  the  mouth, 
and  suspends  the  tongue ; it  arises  from  a ridge  at  the 
root  of  the  alveolar  processes  of  the  lower  jaw  extend- 
ing from  the  last  dens  molaris  to  the  chin.  Its  fibres 
converge  towards  a white  tendinous  line  placed  between 
it  and  its  fellow,  and  extending  from  the  base  of  the 
os  hyoides  to  the  chin.  This  muscle  lies  above  so  as 
to  be  concealed  by  the  anterior  belly  of  the  digastricus, 
and  when  it  contracts,  it  draws  tlie  os  hyoides  upwards 
and  projects  the  tongue. 

The  Genio-Hyoideus  is  immediately  above  the  last, 
by  turning  down  the  anterior  edge  of  which,  it  is  seen. 
It  arises  tendinous  from  the  tubercle  on  the  posterior 
side  of  the  symphysis  of  the  lower  jaw,  and  increasing 
somewhat  in  breadth,  is  inserted  into  the  anterior  pai't 
of  the  base  of  the  os  hyoides. 

It  draws  the  os  hyoides  upwards  and  forwards.  By 
removing  this  muscle  we  bring  into  view 

The  Genio-Hyo-Glossus,  which  arises  also  tendin- 


MUSCLES  AND  FASCIA. 


19 


ous  from  the  tubercle  on  the  inside  of  the  maxilla 
inferior,  near  the  symphysis,  and  is  inserted  into  the 
base  of  the  os  hyoides  and  into  the  tongue  its  whole 
length,  constituting  a part  of  its  substance.  The  mus- 
cles of  the  opposite  sides  are  in  contact  and  throw  the 
tongue  into  a great  variety  of  positions,  according  to 
the  fibres  which  are  brought  into  action. 

The  Hyo-Glossus  is  just  on  the  exterior  of  the  last. 
It  arises  from  the  base  and  part  of  the  cornu  of  the  os 
hyoides  broad  and  fleshy,  and  is  inserted  into  the  side 
of  the  tongue.  It  draws  the  tongue  inwards  and  down- 
wards. 

The  Lingualis  may  also  be  seen  in  part  in  this  dis- 
section. It  is  one  of  the  intrinsic  mfiscles  of  the  tongue, 
and  lies  on  the  outer  side  of  the  last.  For  a further 
account  of  the  muscles  of  the  tongue,  see  the  article 
Mouth. 

There  are  four  pairs  of  muscles  situated  behind  the 
pharynx  and  oesophagus  close  to  the  cervical  vertebrae, 
which  can  only  be  seen  imperfectly  in  this  dissection. 

1.  The  Longus  Colli  is  next  to  the  middle  line 
of  the  vertebrae,  and  arises  from  the  sides  of  the  bodies 
of  the  three  superior  vertebrae  of  the  back,  and  from 
the  anterior  edges  of  the  transverse  processes  of  the 
five  lower  cervical  vertebrae.  Its  fibres  pass  somewhat 


20 


OF  THE  HEAD  AND  NECK. 


obliquely  upwards  and  inwards  to  be  inserted  into  the 
front  of  the  bodies  of  all  the  cervical  vertebrae. 

It  bends  the  neck  forwards  and  to  one  side. 

2.  The  Rectus  Capitis  Interxus  Major  arises 
tendinous  and  fleshy  from  the  fronts  of  the  transverse 
processes  of  the  third,  fourth,  fifth  and  sixth  cerrical 
vertebrae,  forms  a considerable  fleshy  belly,  and  is  in- 
serted into  the  cuneiform  process  of  the  os  occipitis  just 
before  the  condyle.  It  is  placed  on  the  outside  of  the 
longus  colli,  and  bends  the  head  forwards. 

3.  The  Rectus  Capitis  Internus  Minor  arises 
fleshy  from  the  front  of  the  body  of  the  first  cerrical 
vertebra  near  its  transverse  process,  and  is  inserted 
under  the  rectus  major  before  the  root  of  the  condy- 
loid process  of  the  occipital  bone. 

It  bends  the  head  forwards. 

4.  The  Rectus  Capitis  Lateralis  arises  fleshy 
from  the  front  of  the  transverse  process  of  the  atlas, 
and  is  inserted  tendinous  and  fleshy  into  the  ridge  on 
the  outside  of  the  condyle  of  the  occiput,  leading  from 
it  to  the  mastoid  process.  It  pulls  the  head  a little  to 
one  side. 

On  the  outside  of  these  muscles,  passing  from  the  ex- 
terior edges  of  the  cervical  vertebi’se  to  the  upper  parts 


MUSCLES  AND  FASCIA. 


21 


of  the  thorax,  are  the  Scaleni  muscles,  three  in  num- 
ber, and  named  from  their  situation. 

1.  The  Scalenus  Anti cus  arises  by  three  distinct 
tendinous  heads  from  the  transverse  processes  of  tlie 
fourth,  fifth  and  sixth  cervical  vertebrse,  and  is  insert- 
ed tendinous  and  fleshy  into  the  upper  edge  of  the  first 
rib  just  anteriorly  to  its  middle. 

2.  The  Scalenus  Medius  arises  by  distinct  ten- 
dons from  the  transverse  processes  of  all  the  cervical 
vertebrse,  and  is  inserted  tendinous  and  fleshy  into  the 
the  upper  part  of  the  first  rib,  in  all  the  space  from  its 
middle  to  its  tubercle. 

3.  The  Scalenus  Posticus  arises  from  the  trans- 
verse processes  of  the  fifth  and  sixth  cervical  vertebrse, 
and  is  inserted  into  the  upper  face  of  the  second  rib 
just  anterior  to  its  tubercle. 

These  muscles  are  concealed  by  the  sterno-cleido-mas- 
toideusand  the  anterior  edge  of  the  trapezius;  to  be 
well  seen,  the  clavicle  should  be  loosened  from  the  ster- 
num and  thro\vn  off  to  one  side.  The  third  Scalenus 
is  best  seen  in  dissecting  the  muscles  of  the  spine,  and 
resembles  very  much  one  of  that  class  to  which  Albinus 
gives  the  name  of  Levatores  Costarum.  All  the  Scaleni 
elevate  the  ribs  and  bend  the  neck  to  one  side.  They 
are  particularly  interesting  as  connected  with  the  course 
of  the  large  blood-vessels  and  nerves  of  the  upper  ex- 


22 


OF  THE  HEAD  AND  NECK. 


tremity,  which  will  be  more  particularly  alluded  to  iu 
the  dissection  of  the  axilla. 

This  is  a proper  place  also  for  looking  at  the  Pterygoid 
muscles;  they  are,  however,  but  imperfectly  seen.  The 
only  way  to  get  a very  good  view  of  them  is  to  make 
the  dissection  on  a vertical  section  of  the  head,  or  on  a 
head'detached  from  the  cervical  vertebrae,  which  can 
be  done  very  conveniently  when  we  are  engaged  in  the 
study  of  the  nose,  or  of  the  pharynx. 

The  Pterygoideus  Externus  arises  fleshy  from 
the  outer  side  of  the  external  pterygoid  process  of  the 
sphenoid  bone,  from  the  tuber  of  the  upper  maxilla,  and 
from  the  under  surface  of  the  temporal  process  of  the 
sphenoid  bone.  It  passes  outwards  and  backwards  hori- 
zontally, and  is  inserted  into  the  inner  side  of  the  neck 
of  the  inferior  maxilla  and  into  the  capsidar  ligament  of 
the  articulation. 

The  Pterygoideus  Ixternus  arises  by  tendinous 
and  fleshy  fibres  from  the  internal  plate  of  the  ptery- 
goid process  of  the  sphenoid  bone  at  the  outer  side  of 
the  Eustachian  tube.  It  fills  up  the  most  of  the  ptery- 
goid fossa,  and  passing  downwards  and  backwards,  is 
inserted  tendinous  and  fleshy  into  the  interior  face  of 
the  angle  of  the  lower  jaw. 

Both  of  these  muscles  are  important  in  mastica- 


GLANDS. 


23 


t’lon^  they  close  the  jaws,  throw  the  lower  one  forward, 
and  produce  the  grinding  motion  by  acting  alternately. 


SECTIO^'  II. 

Of  the  Glands  of  the  Head  and  JWek. 

The  Thyroid  Grand,  (Gland.  Thyroidea,)  consist- 
ing of  two  lobes  united  by  an  isthmus,  is  placed  on  each 
side  of  the  upper  part  of  the  trachea,  extending  up- 
wards laterally  by  the  cricoid  cartilage  to  the  thyroid. 
It  resembles  a pair  of  saddle-bags  in  its  general  outline, 
the  upper  edge,  however,  being  very  much  excavated 
or  crescentic,  with  the  horns  pointing  upwards.  The 
isthmus  passes  over  the  second  ring  of  the  trachea,  and 
is  firmly  fixed  to  it  by  a short  cellular  substance.  Duver- 
ney  and  Soemmoring  in  their  plates  represent  a muscle, 
passing  on  the  left  side  of  the  larynx,  from  the  base  of 
the  os  hyoides  to  the  upper  edge  of  the  thyroid  gland, 
to  which  they  give  the  name  of  Muscidus  Glandulse 
Thyroidese.  Its  occurrence  in  this  country  is,  I pre- 
sume, exceedingly  rare,  as  out  of  several  hundred  sub- 
jects which  I have  superintended  the  dissection  of,  but 
one  example  of  it  has  been  noticed. 

It  may  be  observed,  however,  that  a process  of  the 
isthmus  looking  like  a muscular  slip  is  frequently  form- 
ed on  the  left  side,  and  goes  up  to  the  base  of  the  os 


24 


OF  THE  HEAD  AND  NECK. 


hyoides,  and  that  sometimes  a few  filaments  are  detach- 
ed to  the  gland  from  the  thyreo -hyoid  or  crico  hyoid 
muscles. 

This  gland  is  covered  by  the  sterno- hyoid  and  thyroid 
muscles.  It  is  of  a dark  brown  colour,  has  a capsule 
from  the  contiguous  cellular  membrane  or  fascia,  be- 
sides its  own  proper  coat.  The  structure  of  it  is  very 
imperfectly  understood;  the  most  that  we  know  is,  that 
it  is  extremely  vascular;  when  cut  into  or  inflated 
it  exhibits  a great  number  of  cells  communicating  with 
each  other,  of  different  sizes,  and  containing  an  unctu- 
ous and  somewhat  transparent  fluid,  and  that  it  has  no 
excretory  duct. 

On  each  side  of  the  neck  are  three  large  salivary 
glands,  the  Parotid — the  Submaxillary — and  the  Sub- 
lingual. 

The  Parotid  Glaxd  (GlandulaParotis)  isthemost 
considerable  of  the  three,  and  its  form  is  very  irregu- 
lar, depending  on  the  space  into  which  it  is  crowded.  It 
reaches  from  the  zygoma  downwards  to  tlie  angle  of  the 
jaw,  occupying  the  space  from  the  mastoid  process  and 
meatus  auditorius  to  the  ramus  of  the  jaw,  and  extend- 
ing from  the  skin  externally  to  the  styloid  process, 
styloid  muscles  and  the  tendon  of  the  digastricus 
internally ; it  is  there  only  separated  from  the  internal 
carotid  artery  by  these  parts  internally ; its  connexions 
are  numerous  and  exceedingly  intricate.  It  is  removed 
in  the  dead  subject  from  the  contiguous  parts  with  great 
difficulty,  and  in  the  living  subject  its  complete  and  safe 


GLANDS. 


25 


extirpation  is  probably  impracticable.  The  portio  dura 
nerve  and  several  large  branches  of  the  external  caro- 
tid have  to  penetrate  directly  through  its  substance  in 
order  to  arrive  at  their  destinations. 

It  has  been  observed  that  this  gland  is  covered  exter- 
nally by  an  extension  of  the  fascia  superficialis  of  the 
neck ; from  the  interior  face  of  this  fascia  many  prolon- 
gations are  sent  out,  which  penetrate  the  gland  in  every 
direction,  separating  its  lobules  from  each  other  and 
conducting  the  blood-vessels  and  nerves  through  its  sub- 
stance. The  substance  of  the  gland  is  formed  of  small 
rounded  granulations  of  a light  pink  colour,  united  into 
lobules  of  various  forms;  an  arteriole  may  be  injected, 
going  to  each  of  them. 

The  parotid  gland  is  elongated  at  its  anterior  mar- 
gin into  a point,  lying  on  the  posterior  part  of  the  mas- 
seter  muscle.  From  the  upper  part  of  this  point  pro- 
ceeds the  parotid  duct  across  the  masseter  muscle, 
about  eight  lines  below  the  zygoma;  and  according 
to  the  observations  of  Dr.  Physick,  in  a line  from  the 
under  part  of  the  lobe  of  the  ear  to  the  tip  of  the  nose. 
The  parotid  duct,  (Ductus  Stenonianus, ) is  about  the  size 
of  a crow  quill ; it  arises  from  the  granulations  of  the 
gland,  by  ramuscles  which,  unite  successively,  to  form 
it.  The  gland  is  sometimes  divided  into  two  lobes,  in 
which  case  each  has  an  excretory  duct  that  joins  the 
other,  half  an  inch  in  front  of  the  anterior  edge  of 
the  gland.  The  common  duct  lies  close  to  the  masse- 
ter muscle,  and  may  easily  be  overlooked  by  the  young 

D 


36 


OF  THE  HEAD  AND  NECK. 


anatomist ; forwards  it  dips  over  the  edge  of  this  mus- 
cle into  a fatty  mass  between  it  and  the  buccinator,  and, 
perforating  the  latter,  has  its  orifice  in  the  mouth, 
opposite  the  second  large  molar  tooth  of  the  upper 
jaw. 

At  the  posterior  part  of  this  duct,  between  it  and  the 
zygoma,  a small  gland,  is  situated,  varying  in  its  size 
and  form,  and  called  by  Haller  the  accessory  of  the 
parotid.  It  is  not  always  found. 

The  Submaxillary  Glakd  (Gland.  Sub-Maxil- 
laris)  is  irregularly  ovoid.  It  is  situated  below  the  mus- 
culus  cutaneus  in  the  space  bounded  by  the  digastric 
muscle  below,  the  mylo  hyoid  towards  the  mouth,  and 
the  body  of  the  lower  jaw  externally, — and  is  in  con- 
tact with  the  facial  ?irtery.  It  almost  touches  the  paro- 
tid gland  behind,  being  separated  from  it  only  by  the 
septum  sent  in  from  the  fascia  superiicialis,  and  at  the 
posterior  edge  of  the  mylo  hyoideus  it  touches  the  sub- 
lingual gland. 

Its  structure  is  the  same  with  that  of  the  parotid 
gland,  except  the  capsule  of  cellular  membrane  with 
its  internal  -prolongations,  being  much  looser.  It  has 
an  excretory  duct,  (Ductus  Whartoiiianus, ) arising  in 
the  same  way  by  ramuscles,  but  much  thhiuer  and 
more  extensible  than  the  parotid  duct ; it  peneti’ates 
between  the  back  edge  of  the  mylo  hyoid  and  the  hyo- 
glossus  muscles,  and  continues  between  tlie  genio-hyo- 
glossus  and  the  sublingual  gland  : from  the  latter  it  re- 


GLANDS. 


27 


ceives  occasionally  several  branches,  it  terminates  by 
an  orifice  on  the  side  of  the  fraenum  linguae  near  its 
anterior  edge. 

The  Sublingual  Gland  (Glandula  Sublingualis) 
is  placed  under  the  lining  membrane  of  the  mouth  be- 
tween the  side  of  the  tongue  and  the  mylo  hyoid  mus- 
cle, and  being  oblong  it  is  parallel  with  the  genio-hv|>- 
glossus  where  the  latter  is  about  to  join  the  tongue. 

This  gland  is  not  uniform  in  the  arrangement  of  its 
excretory  ducts.  Sometimes  it  has  fifteen  or  twenty 
excretory  orifices  in  the  lining  membrane  of  the  mouth; 
on  other  oecasions  several  of  these  short  ducts  are  col- 
lected into  one  or  two  principal  trunks  which  open 
either  direetly  into  the  mouth  or  into  the  duct  of  Whar- 
ton. By  turning  up  the  tip  of  the  tongue,  the  pro- 
jection of  this  gland  is  readily  seen,  as  well  as  several 
salivary  granulations,  or  little  glands,  which  border 
on  it. 

Lymphatic  Glands.  Medical  men  are  often  con- 
sulted on  the  subject  of  indurated  and  not  very  pain- 
ful swellings  in  the  neck,  which  most  frequently  are 
enlarged  lymphatic  glands.  In  a course  of  dissections 
these  should  by  no  means  be  overlooked,  as  they  are 
very  numerous.  They  vary  much  in  size  and  number; 
being  for  the  most  part  flattened  ovals,  some  are  not 
more  than  two  lines  in  their  long  diameters;  others 


28 


OF  THE  HEAD  AND  NECK. 


are  nine  or  ten  lines  long.  They  are  both  superficial 
and  deep-seated. 

Between  the  skin  and  the  insertion  of  the  stenio- 
mastoid  muscle  there  are  from  four  to  six ; in  the  inter- 
stice just  above  the  clavicle  between  the  posterior  edge 
of  the  sterno-mastoid  muscle  and  the  anterior  edge  of 
the  trapezius,  bordering  on  the  external  jugular  vein, 
tl^^re  are  half  a dozen.  Between  the  skin  and  the  paro- 
tid gland  there  are  two,  one  above  and  the  other  below. 
On  the  submaxillary  gland,  and  at  its  anterior  and  pos- 
terior extremities,  there  are  eight  or  nine.  It  is  sup- 
posed, by  respectable  surgeons,  that  the  reputed  cases 
of  extirpation  of  the  parotid  and  of  the  submaxillary 
gland,  have  amounted  actually  only  to  the  removal  of 
some  of  these  lymphatic  glands  in  a state  of  enlarge- 
ment. 

The  deep-seated  lymphatic  glands  are  also  very 
abundant;  along  the  course  of  the  great  cer^*ical  ves- 
sels, but  principally  between  them  and  the  anterior 
edge  of  the  trapezius  muscle,  there  are  about  twenty. 
Between  the  lower  edge  of  the  thyroid  gland  and  the 
sternum  on  the  trachea  there  are  four,  and  this  chain 
is  continued  downwards  towards  the  heart  by  the  exist- 
ence of  several  on  the  side  of  the  oesophagus,  trachea, 
and  great  blood-vessels. 


BLOOD  VESSELS. 


29 


Section  III, 

Of  the  Blood-vessels  of  the  JVeck  and  Head. 

The  Right  Carotid  Artery  is  a branch  of  the 
arteria  innominata,  and  the  left  a branch  of  the  aorta; 
their  course  differs  somewhat  at  first,  the  right  be- 
ing more  oblique,  afterwards  the  course  and  distribu- 
tion are  uniform  in  both.  A regular  ascent  is  perform- 
ed in  front  of  the  cervical  vertebrae  at  the  side  of  the 
oesophagus  and  pharynx,  no  branch  being  sent  off  till 
the  carotid  is  near  the  os  hyoides  and  just  below  its 
cornu.  Here  it  divides  into  two  branches  of  nearly 
equal  size,  the  internal  and  the  external  carotid ; the  first 
is  intended  for  the  brain,  and  the  last  for  the  external 
parts  of  the  neck  and  head.  In  the  lower  part  of  the 
neck  the  carotid  is  covered  by  the  sterno  hyoideus  and 
thyroideus  and  the  anterior  edge  of  the  sterno-cleido- 
mastoideus,  and  at  an  inch  and  a half  below  its  bifurcation 
it  is  crossed  obliquely  by  the  omo-hyoideus  muscle. 
This  point  may  be  ascertained  before  the  skin  is  open- 
ed by  a horizontal  line  drawn  across  the  neck  over  the 
first  ring  of  the  trachea,  and  consequently  below  the 
larynx.  In  its  whole  course  it  is  involved  with  the  par 
vagum,  sympathetic  and  descendens  noni  nerves. 

Parallel  with  the  larynx  the  carotid  may  be  felt  pul- 


30 


OF  THE  HEAD  AND  NECK. 


sating  very  distinctly,  being  there  covered  only  by  the 
pjatysma  myoides.  It  is  contained  in  a sheath  of  con- 
densed cellular  membrane  common  to  it,  the  internal 
jugular  vein  and  the  par  vagum  nerve. 

The  External  Carotid,  (Carotis  Externa)  at  the 
place  of  bifurcation,  is  interior  and  anterior  to  the  in- 
ternal carotid,  and  it  immediately  begins  to  send  oft' 
branches  as  follow : 

1.  The  Arteria  Thyroidea  Superior  passes  in  a 
meandering  dii’ection  to  its  principal  destination  tlie 
thyroid  gland,  through  which  it  is  minutely  distribut- 
ed, anastomosing  freely  with  the  other  arteries  of  the 
same  body.  In  its  course  it  sends  off  the  larjmgeal 
branch,  which  penetrates  to  the  muscles  of  the  larynx, 
either  between  the  os  hyoides  and  thyroid  cartilage  or 
the  thyroid  and  cricoid.  It  also  sends  off  some  smaller 
branches  to  contiguous  parts. 

2.  The  Arteria  Lingualis  arises  just  above  tlic 
last ; it  goes  very  near  the  cornu  of  the  os  hyoides. 
crossing  it  obliquely  by  penetrating  the  hyo-glossus 
muscle.  At  the  root  of  the  tongue  it  sends  off  a trans- 
verse branch  (the  Dorsalis  Linguae),  and  a little  furtlier 
forwards  it  divides  into  two  branches,  one  going  to  the 
Sublingual  Gland  (the  Ramus  Sublingualis),  the  otlier 
distributed  through  the  tongue  (the  Ranina). 


BLOOD  VESSELS. 


31 


3.  The  Arteria  Factalis  arises  near  and  above 
the  other;  it  is  tortuous,  passing  under  the  stylo  hyoid 
and  the  tendon  of  the  digastric  muscle.  It  is  much  in- 
volved with  the  submaxillary  gland,  to  which  it  sends 
branches.  The  submental  branch  arises  from  it  here, 
which  passes  forwards  to  the  symphysis  of  the  jaw, 
near  the  exterior  margin  of  the  mylo  hyoid  muscle. 

The  Arteria  Facialis  mounts  over  the  lower  jaw  just 
before  the  masseter  muscle ; to  the  latter  it  sends  a 
branch ; fowards  it  sends  another  towards  the  front  of 
the  chin  called  Inferior  Labial.  On  a line  with  the  cor- 
ner of  the  modth,  it  sends  to  the  lips  the  Inferior  and 
the  Superior  Coronary  Arteries,  which  are  very  tortu- 
ous and  surround  the  mouth,  anastomosing  freely  with 
those  of  the  other  side. 

After  this  the  facial  artery  ascends  to  the  internal 
canthus  of  the  eye,  sending  off  intermediately  a branch 
to  the  ala  nasi,  and  another  which  anastomoses  with  the 
inferior  orbitar  artery  ; at  the  internal  canthus  it  anas- 
tomoses with  branches  from  the  ophthalmic  and  termi- 
nates. 

4.  The  Arteria  Pharyngea  Inferior  arises  from 
the  carotid  opposite  to  the  lingual ; it  is  small,  being  dis- 
tributed on  the  pharynx  and  sending  a branch  upwards 
through  the  foramen  lacerum  to  the  dura  mater 

5.  The  Arteria  Occipitalis  is  large,  and  arises  op- 
posite to  the  facial  and  sometimes  higher  u]i.  It  crosses 


32 


OF  THE  HEAD  AND  NECK. 


over  the  internal  jugular  vein  and  the  eighth  pair  of 
nerves,  passes  the  base  of  the  cranium  under  the  inser- 
tion of  the  muscles  going  to  the  mastoid  process,  and 
is  distributed  to  the  parts  lying  on  the  occipital  bone, 
its  upper  branches  anastomose  with  those  of  the  tem- 
poral artery. 

Its  collateral  branches  are,  one  to  the  dura  mater 
through  the  posterior  foramen  lacerum,  or  the  mas- 
toid foramen,  another  to  the  interior  parts  of  the  ear, 
and  a considerable  one  to  the  complexus  and  adjacent 
muscles  of  the  neck. 

6.  The  Posterior  Auris,  or  Arteri  a Stylo  M as- 
TOiDEA,  arises  from  the  carotid  at  the  lower  edge  of  the 
parotid  gland,  and  passes  backwards  and  upwards  be- 
tween the  meatus  externus  and  the  mastoid  process,  to 
terminate  behind  the  ear.  It  is  distributed  principally 
to  the  contiguous  superficial  parts,  but  one  branch  goes 
up  the  stylo  mastoid  foramen,  to  the  tympanum  and  to 
the  labyrinth. 

The  External  Carotid,  while  detaching  these 
branches,  becomes  very  deeply  situated  under  the  di- 
gastric and  stylo-hyoid  muscles,  and  the  inferior  end  of 
the  parotid  gland;  afterwards  it  penetrates  the  sub- 
stance of  the  gland,  becoming  much  involved  in  it,  and 
sending  off  several  small  twigs.  It  ascends  through  the 
gland  and  exhibits  itself  superficially  just  before  the 
meatus  externus,  in  mounting  over  the  root  of  the  zygo- 


BI.OOD  VESSELS. 


33 


ma.  When  on  a line  with  the  neck  of  the  jaw  bone 
it  sends  off  a very  large  branch,  the  internal  maxiljary, 
to  the  parts  underneath  the  ramus  of  the  bone.  The 
origin  of  this  branch  is  to  be  considered  as  the  termina- 
tion of  the  name  external  carotid,  and  the  trunk  is 
afterwards  called  temporal. 

The  Arteria  Temporalis  goes  to  the  side  of 
the  head ; while  it  is  still  bedded  in  the  parotid,  it 
sends  off  the  Transversalis  Faciei,  which  crosses  the 
masseter  muscle  below  the  Parotid  Duct,  and  is  distri- 
buted to  the  contiguous  parts.  The  temporal  artery 
then  rises  over  the  zygoma,  where  a branch  leaves  it 
which  penetrates  the  temporal  fascia,  and  is  distributed 
to  the  muscle  beneath,  this  is  the  middle  temporal  artery. 

The  temporal  artery  having  got  an  inch  or  so  above 
the  zygoma,  divides  into  an  anterior  and  a posterior 
branch . The  first  is  distributed  forwards  on  the  temple, 
inosculating  with  its  fellow  of  the  other  side,  and  with 
the  facial  and  the  ophthalmic  artery.  The  second  is 
distributed  laterally  on  the  parietal  region,  also  anasto- 
mosing with  its  fellow  of  the  opposite  side  and  with  the 
occipital  artery. 

The  Arteria  Maxillaris  Interna  can  be  got  at 
only  by  removing  the  ramus  of  the  jaw  j it  winds  around 
the  neck  of  the  inferior  maxilla,  and  proceeds  in  a very 
tortuous  manner  to  the  bottom  of  the  zygomatic  fossa^ 
touching  in  its  course,  the  inferior  surface  of  the  tem- 

E 


34 


OF  THE  HEAD  AND  NECK. 


poral  bone.  It  passes  between  the  intenial  and  exter- 
nal pterygoid  muscles  immediately  after  leardng  the 
carotid  artery;  and  sends  off,  several  branches,  gene- 
rally in  the  following  order ; 

1.  To  the  cavity  of  the  tympanum  through  the  gle- 
noid fissure. 

2.  The  lesser  meningeal,  to  the  dura  mater  through 
the  foramen  ovale. 

3.  The  gi’eater  meningeal,  to  the  dura  mater  through 
the  foramen  spinale.  From  this  trunk  sometimes  pro- 
ceeds the  lesser  meningeal  to  the  dura  mater  through 
the  foramen  ovale. 

4.  The  inferior  maxillary,,  to  the  teeth  of  the  lower 
jaw  through  the  posterior  m.ental  foramen. 

5.  Two  branches  to  the  temporal  muscle,  the  first  is 
the  posterior  deep,  the  second  the  anterior  deep  tempo- 
ral artery. 

6.  Branches  to  the  pterygoid  muscles  and  to  the 
masseter. 

7.  A branch  to  the  buccinator  and  zygomaticus  major. 

8.  The  alveolar  artery  to  the  great  and  small  molar 
teeth  of  the  upper  jaw. 

9.  The  infi’a  orbitar,  through  the  infra  orbitar  canal 
to  the  canine  and  incisor  teeth,  and  to  the  cheek. 

10.  The  superior  palatine  artery  through  the  poste- 
rior palatine  canal  to  the  soft  palate. 

11.  The  superior  pharyngeal  artery  to  the  upper 
part  of  the  pharynx. 

12.  The  spheno  palatine,  which  is  the  terminating 


BLOOD  VESSELS. 


35 


branch  to  the  internal  maxillary  artery,  and  is  very 
minutely  distributed  to  the  Schneiderian  membrane  by 
two  trunks,  one  on  the  septum  of  the  nose,  and  the 
other  on  its 'external  side. 

The  Internal  Carotid  Artery,  (Carotis  Interna) 
at  its  comnmncement,  is  generally  dilated  like  an  inci- 
pient aneurism ; it  curves  much  in  getting  to  the  fora- 
men caroticum,  and  is  in  contact  with  the  par  vagum 
and  sympathetic  nerves;  it  sends  off  no  intermediate 
branches.  In  the  canal,  it  gives  a branch  to  the  tym- 
panum, and  as  it  lies  on  the  side  of  the  sella  turcica,  it 
gives  the  anterior  and  posterior  arteries  of  the  caver- 
nous sinus.  Its  subsequent  history  is  merged  in  that  of 
the  ophthalmic  and  cerebral  arteries. 

The  following  arteries  belonging  to  the  neck  are  de- 
rived from  the  subclavian,  as  it  is  about  to  get  between 
the  scaleni  muscles. 

1.  The  Arteria  Vertebralis  which  goes  into  the 
canal  of  the  transverse  processes  of  the  neck  at  the  sixth 
vertebra,  and,  following  its  course,  enters  the  foramen 
magnum  occipitis  to  be  distributed  to  the  brain.  It  is 
very  tortuous  at  the  first  and  second  vertebrae. 

2.  The  Arteria  Thyroidea  Inferior,  which 
passes  up  obliquely  to  the  thyroid  gland  between  th,e 
great  vessels  of  the  neck  and  the  vertebrae ; in  its  dis- 


36 


OF  THE  HEAD  AND  NECK. 


tributioii  it  anastomoses  very  freely  with  the  othei- 
thyroid  arteries. 

3.  The  Cervicalis  Anterior,  a small  artery,  and 
which  is  distributed  along  the  course  of  the  scaleni  mus- 
cles. It  comes  frequently  from  the  inferior  thyroid,  or 
some  other  branch  of  the  subclavian. 

4.  The  Cervicalis  Posterior;  it  is  vei’y  tortuous, 
and  runs  horizontally  across  the  root  of  the  neck,  to  the 
trapezius  muscle  and  the  subjacent  ones.  It  arises  most 
frequently,  either  from  the  subclavian  or  the  inferior 
thyroid. 

The  Veins  of  the  Face  and  external  parts  of  the 
Head  correspond  so  nearly  with  the  distribution  of  the 
arteries,  that  they  may  be  considered  as  having  the 
same  course;  to  undertake  the  description  of  them,  there- 
fore, would  be  almost  a repetition  of  what  has  been 
said. 

Towards  the  angle  of  the  jaw  they  are  collected  into 
a common  trunk,  the  external  jugular  (Jugularis  Ex- 
terna,) which  crosses  obliquely  the  sterno-cleido-mastoid 
muscle  under  the  platysma  myoides  in  the  direction  of 
the  fibres  of  the  latter,  and  runs  into  the  subcla\Tan  vein 
just  behind  the  clavicle  at  the  posterior  edge  of  the 
sterno-cleido-mastoid  muscle.  Sometimes  the  external 
jugular,  almost  immediately  after  its  formation,  joins 
the  internal  jugular.  On  other  occasions  the  facial  vein 


BLOOD  VESSELS. 


37 


joins  the  external  jugular;  and  the  temporal  vein,  with 
slight  accessions  from  the  side  of  the  face,  forms  a trunk 
which  descends  almost  vertically  under  the  platysma 
myoides  and  outside  of  the  sterno-cleido-mastoideus 
to  join  the  subclavian  vein  in  front  bf  the  scaleni  mus- 
cles. The  varieties  are  in  short,  too  numerous  to  be 
recounted  in  this  work. 

The  Internal  Jugular  Vein  (Jugularis  Interna) 
may,  with  propriety,  be  considered  as  the  great  venous 
trunk  of  the  brain,  being  a continuation  of  the  lateral  si- 
nus. It  lies  on  the  outside  of  the  internal  and  of  the 
common  carotid  artery,  enclosed  in  the  same  sheath,  de- 
scends into  the  upper  mediastinum  in  contact  with  the 
pleura,  and  is  joined  at  the  internal  edge  of  the  scale- 
nus anticus  muscle  by  the  subclavian  vein.  This  jugu- 
lar vein  is  occasionally  much  dilated,  and  in  the  con- 
tractions of  the  right  auricle,  spreads  over  the  carotid 
artery.  One  vein  is  sometimes  much  larger  than  the 
other. 

The  Upper  Thyroidal  Veins  discharge  into  the 
internal  or  external  jugulars;  the  Lower  Thyroidal 
Veins  into  the  transverse  or  subclavian  veins ; some- 
times a trunk  is  formed  across  the  upper  edge  of  the 
sternum  from  one  subclavian  to  the  other,  and  above  the 
great  transverse  vein ; into  this  the  inferior  thyroidal 
veins  discharge  in  whole  or  in  part.  The  variety  of 
arrangement  is  here  also  too  great  to  admit  of  a standard 
description. 


38 


NERVES  OF  THE  HEAD  AND  NECK. 


Section  IV, 

Of  the  JVerves  of  the  Head  and  Aeck. 

A JiiNUTE  dissection  of  these  will  scarcely  be  under- 
taken by  the  young  student ; to  perform  it  successfully 
requires  much  time,  patience,  and  address ; when,  by  ad- 
vanced study,  the  two  latter  are  obtained,  the  labour  will 
be  fully  compensated,  by  the  pleasure  and  information 
it  affords.  For  a very  minute  dissection  a lean  subject 
is  indispensable ; for  a common  one,  it  is  less  important, 
and  much  of  the  dissection  may  be  performed  on  the 
subject  appropriated  to  the  arteries. 

The  PoRTio  Dura  comes  out  at  the  stylo-mastoid 
foramen,  is  almost  immediately  afterwards  deeply  invol- 
ved in  the  parotid  gland,  and  di\udes  into  fasciculi  in 
its  substance.  Emerging  at  different  points  it  is  dis- 
tributed very  minutely  on  the  side  of  the  face,  sending 
branches  to  the  temple  which  join  those  of  the  supra- 
orbitar  nerve,  branches  to  tlie  cheek  which  join  those 
of  the  infra-orbitar  nerve,  branches  to  the  chin  which 
join  those  of  the  inferior  maxillary  nerve,  and  brandies 
to  the  upper  part  of  the  neck,  which  join  those  of  the 
superior  cervical  nerves. 


NERVES. 


39 


Tlie  distribution  of  this  nerve  is  too  minute  to  admit 
of  more  than  a general  reference  to  it.  Its  branches 
join  each  other  frequently,  forming  the  net-work  call- 
ed pes  anserinus.  The  dissection  of  it  should  be  com- 
menced at  the  stylo-mastoid  foramen,  or  in  the  parotid 
gland,  and  the  skin  should  be  raised  only  as  its  branches 
are  exposed;  without  this  precaution  the  dissection 
will  fail. 

The  Trigeminus,  or  Fifth  Pair  of  Nerves,  comes 
next.  Its  branches  are  brought  into  view  by  sawing 
off  the  ramus  of  the  lower  jaw  and  detaching  it  entirely, 
observing  to  leave  the  pterygoid  muscles  by  cutting 
close  to  the  bone  through  their  insertions ; when  the 
adipose  and  cellular  membrane  is  then  cleared  away, 
the  second  and  third  branches  of  this  nerve  are  seen 
deep  in  the  bottom  of  the  zygomatic  fossa.  For  the  dis- 
tribution of  the  first  or  ophthalmic  trunk,  see  the 

Auxiliary  parts  of  the  eye.” 

The  Second,  or  Superior  Maxillary  branch  of 
the  Fifth,  comes  out  of  the  cranium  through  the  fora- 
men rotundum,  and  is  firet  seen  in  the  upper  part  of 
the  pterygoid  fossa.  It  immediately  sends  forwards  a 
branch  into  the  infra-orbitar  canal  of  the  upper  jaw 
bone,  which  passes,  through  it,  comes  out  at  the  infra- 
orbitar  foramen,  and  terminates  by  branches  on  the 
cheek.  This  is  the  infra-orbitar  nerve,  which  just  be- 
fore entering  the  canal,  sends  off  two  twigs  to  supply 


40 


OF  THE  HEAD  AND  NECK. 


the  three  or  four  last  molares,  and  which  forwards  sends 
off  the  anterior  dental  nerve  to  supply  the  small  mo- 
larj  canine,  and  incisor  teeth. 

Afterwards,  the  Superior  Maxillary  Nerve  passes 
downwards  in  two  divisions,  to  a level  with  the  spheno 
palatine  foramen ; here  they  unite,  form  the  spheno  pala- 
tine ganglion,  or  the  ganglion  of  Meckel,  from  which 
proceed  the  Pterygoid,  the  Lateral  Nasal,  and  the  Pa- 
latine Nerves. 

The  Pterygoid  Nerve,  retrograding  through  the 
foramen  of  the  same  name,  gets  into  the  cavity  of  the 
cranium  through  the  anterior  foramen  lacerum  at  the 
point  of  the  petrous  portion  of  the  temporal  bone  and 
there  divides;  one  branch  joins  the  carotid  artery, 
(see  Sympathetic  Nerve,)  and  the  other  passing  into 
the  vidian  foramen  has  a singular  course  through  the 
ear.  (See  Chorda  Tympani.) 

The  Lateral  Nasal  Nerve  consists  of  several 
filaments  passing  from  the  spheno  palatine  ganglion;  get- 
ting into  the  nose  they  are  distributed  to  the  pituitary 
membrane  of  the  outside  of  the  nose,  and  also  to  the  same 
membrane  which  covers  the  septum.  One  of  the 
branches  of  the  latter  makes  a long  sweep,  dips  into  the 
foramen  incisivum,  and,  according  to  M.  J.  Cloquet, 
forms  a ganglion  with  its  fellow  near  the  bottom  of  the 
canal.  With  this  ganglion  communicate  branches  of 
the  palatine  nerve. 


NERVES. 


41 


The  Palatine  Nerve  passes  through  the  posterior 
palatine  canal  to  the  roof  of  the  mouth;  it  there  divides 
into  filaments  supplying  the  lining  membrane,  the  soft 
palate,  the  uvula,  and  the  tonsils.  In  its  way  down- 
wards, it  sends  several  small  twigs  to  that  portion  of 
the  pituitary  membrane  which  covers  the  inferior  tur- 
binated bone. 

The  Inferior  Maxillary  Nerve,  or  the  Third 
Branch  of  the  Fifth  Pair,  comes  through  the  foramen 
ovale  into  the  zygomatic  fossa,  and  divides  immediately 
into  two  branches,  one  of  which  is  distributed  in  mi- 
nute ramifications  to  the  muscles  of  mastication,  as  the 
pterygoid,  masseter,  and  temporal;  it  also  sends  a 
branch,  the  size  of  a knitting-needle,  which  joins  the 
portio  dura  on  the  face,  and,  in  order  to  get  to  it,  ad- 
heres closely  to  the  neck  of  the  inferior  maxilla. 
This  last  branch,  from  being  blended  with  the  portio 
dura,  must,  of  course,  as  long  as  it  remains  undivided, 
render  nugatory  the  section  of  the  portio  dura  for  tic 
doloureux. 

The  Second  Branch  of  the  Inferior  Maxillary  Nerve 
passes  between  the  pterygoid  muscles  and  divides  into 
two  trunks ; one  of  which  proceeding  to  the  tongue  is 
the  Lingual  or  Gustatory  nerve,  and  the  other  going  to 
the  lower  jaw  bone  is  the  proper  Inferior  Maxillary 
Nerve.  The  first  in  its  progress  between  the  pterygoid 
muscles  is  joined  by  the  chorda  tympani ; it  there  passes 
above  the  mylo-hyoid  muscle  near  the  duct  of  Whar^ 

F 


42 


OF  THE  HEAD  AND  NECK. 


ton,  and  advancing  to  near  the  end  of  tlie  tongue  is 
divided  very  minutely  among  the  papilla.  The  infe- 
rior maxillary  nerve  enters  the  posterior  maxillary  fora- 
men ; but  while  doing  so  despatches  a branch  to  the  sub- 
maxillary gland  and  the  muscles  under  the  jaw;  it 
then  continues  in  a canal  in  the  spongy  part  of  the  bone, 
dismissing  ramifications  to  all  the  teeth  successively. 
Much  of  the  nerve,  however,  which  is  spent  upon  the 
contiguous  muscles,  remains  to  come  out  at  the  anterior 
maxillary  foramen. 

In  order  to  proceed  properly  in  this  dissection  of 
the  Nerves  of  the  Neck,  the  skin  must  be  carefully 
raised  from  the  sterno-clei do-mastoid  muscle;  by  which 
means  we  shall  see  the  spinal  accessory  nerve  emerging 
from  the  muscle,  and  after  having  given  a few  branches 
to  it,  passing  backwards  to  be  distributed  on  the  anteri- 
or edge  of  the  trapezius  muscle. 

By  detaching  the  sterno  mastoid  muscle  from  its 
origin  and  turning  it  aside,  the  spinal  accessory  nerve 
will  be  seen ; coming  from  the  posterior  foramen  lacerum 
where  it  adheres  to  the  Par  Vagum,  Glosso-Pharjmgeal 
and  Ninth  pair ; and  passing  obliquely  behind  the  in- 
ternal jugular  vein  downwards  and  backwards,  in  oMer 
to  reach  the  sterno  mastoid  muscle. 

At  this  stage  of  the  dissection  a multitude  of  nervous 
filaments  is  seen  upon  the  neck  going  to  its  muscles,  in- 
teguments and  other  parts,  and  interwoven  with  its 
blood-vessels.  They  form  an  intricate  plexus  derived 


NERVES. 


43 


from  various  combinations  of  the  eighth  and  ninth  pairs, 
the  sympathetic  and  the  proper  cemdcail  nerves,  the 
detailed  description  of  which  is  too  elaborate  for  a dis- 
sector’s manual.  It  is  best,  therefore,  for  the  atten- 
tion to  be  confined  to  leading  trunks. 

The  Glosso-Pharyngeus  is  a small  nerve  coming 
from  under  the  internal  jugular  vein,  adhering  to  it, 
and  to  the  other  branches  of  the  eighth  pair,  by  con- 
densed cellular  membrane ; it  passes  to  the  tongue  be- 
tween the  stylo-glossus  and  stylo-pharyngeus  muscles, 
and  on  the  outside  of  the  internal  carotid  artery.  F ollow- 
ing  the  course  of  the  stylo-glossus  muscle  at  its  internal 
edge,  it  gets  to  the  root  of  the  tongue,  where  it  is  dis- 
tributed on  its  side  and  middle,  and  to  the  papillge 
maximse.  In  its  course,  it  sends  several  branches  to 
the  muscles  of  the  pharynx,  and  to  its  internal  mem- 
brane. 

The  Ninth  Pair,  or  the  Nervus  Hypoglossus,  is 
also  very  deeply  seated,  where  it  emerges  from  the 
cranium  at  the  anterior  condyloid  foramen.  Adhering 
for  some  distance  to  the  par  vagum,  by  condensed  cellu- 
lar membrane,  it  abandons  the  par  vagum  by  getting 
between  the  internal  carotid  artery  and  the  internal 
jugular  vein,  and  crossing  them  obliquely  about  half  an 
inch  below  the  glosso-pharyngeus.  It  descends  much 
lower  in  the  neck  than  the  glosso-pharyngeal,  forming 
a large  curve  with  the  convexity  downwards.  It  is  the 


44 


OP  THE  HEAD  AND  NECK. 


next  large  nerve  below  the  glosso-pharyngeal,  the  order 
of  descent  being  first  the  lingual  branch  of  the  fiftli  pair, 
the  glosso- pharyngeal  second,  and  the  ninth  nerve 
third. 

In  its  descent  the  Ninth  nerve  winds  externally 
around  the  external  carotid  artery,  just  below  the  ori- 
gin of  the  occipital  artery.  Here  it  is  below  the  pos- 
terior belly  of  the  digastricus,  and  the  stylo  hyoideus. 
It  then  passes  forwards  somewhat  horizontally  under  the 
external  jugidar  vein  towards  the  root  of  the  tongue, 
where  it  is  at  the  side  of  the  hyo-glossus  muscle  a little 
above  the  os  hyoides,  and  crossed  externally  by  the 
stylo  hyoideus  and  the  tendon  of  the  digastricus.  It 
now  ascends  on  the  inside  of  the  mylo  hyoideus,  and 
divides  abruptly  into  many  ramifications  distributed  to 
all  the  muscles  of  the  tongue,  from  the  space  between 
the  genio-hyo-glossus  and  lingualis  muscles. 

Where  the  Ninth  nerve  winds  externally  around 
the  external  carotid,  it  dismisses  the  Descendens  Noni. 
The  latter  descends  externally  along  the  common 
carotid,  connected  with  its  theca  as  far  as  midway  be- 
tween tbe  sternum  and  os  hyoides;  and  unites  \Hth 
ramifications  from,  the  first,  second,  and  third  cervical 
nerves,  to  form  a bow  under  the  sterno  mastoid  muscle. 
Above  this  bow  the  descendens  noni  detaches  branches 
to  the  upper  parts  of  the  sterno  hyoid  and  thyroid  mus- 
cles, and  from  the  bow  branches  proceed  to  the  lowei 
parts  of  these  muscles. 


NERVES. 


45 


The  Par  Va GUM,  an  important  nerve,  is  immediately 
seen  on  separating  the  common  carotid,  and  the  inter- 
nal jugular  from  each  other.  It  lies  in  the  sheath  of 
these  vessels  at  their  back  part  and  between  them. 
Emerging  from  the  cranium  at  the  posterior  foramen 
lacerum  it  is  somewhat  swollen,  adheres  to  the  ninth 
nerve  and  to  the  superior  cervical  ganglion  of  the  inter- 
costal. It  then  leaves  them  after  a short  distance,  as- 
sumes the  position,  just  expressed,  and  maintains  it 
down  the  neck  till  it  reaches  the  upper  margin  of  the 
thorax. 

Shortly  after  quitting  the  cranium,  it  sends  to  the 
middle  constrictor  of  the  pharynx,  the  Nervus  Pharyn- 
geus. 

Just  below  the  pharyngeal  nerve,  the  Laryngeus 
Superior  is  sent  olf,  which  descends  obliquely  under 
the  Internal  Carotid,  and  divides  at  the  posterior  edge 
of  the  thyro-hyoid  membrane  into  an  internal  and  ex- 
ternal branch.  The  former  being  the  largest  and 
above,  proceeds  between  the  os  hyoides  and  the  thy- 
roid cartilage  under  the  thyro-hyoideus  muscle,  to  the 
internal  parts  of  the  larynx  where  it  is  distributed  by 
minute  ramifications  to  the  arytenoid  muscles,  epi- 
glottis and  lining  membrane.  The  external  branch  de- 
scending, is  disposed  of  by  ramifications  to  the  pharynx, 
to  the  lower  part  of  the  larynx,  and  to  the  thyroid 
gland. 

In  the  upper  part  of  the  thorax,  or  the  lower  part 
of  the  neck,  the  par  vagum  abandons  the  common  ca- 


46 


OF  THE  HEAD  AND  NECK. 


rotid,  and  passes  before  the  subclavian  artery  on  the 
right  side,  and  before  the  aorta  on  the  left.  Immedi- 
ately after  passing  these  vessels  it  divides  into  an  an- 
terior and  a posterior  trunk ; the  first  is  the  continu- 
ed par  vagum,  the  second  the  recurrent  or  the  inferior 
laryngeal. 

The  Laryngeus  Inferior  has  the  same  distribution  on 
both  sides,  but  it  is  to  be  observed  that  on  the  right,  it 
winds  around  the  subclavian  artery,  and  on  the  left  it 
winds  around  the  arch  of  the  aorta.  The  nerve  is  then 
deeply  situated  on  the  side  of  the  trachea,  and  ascends 
to  the  larynx,  sending  branches  to  the  trachea,  the 
oesophagus  and  the  thyroid  gland.  It  is  minutely  dis- 
tributed by  terminating  ramifications  to  the  small  mus- 
cles of  the  larynx,  and  to  its  lining  membrane.  One 
of  its  branches  at  the  inferior  part  of  the  larynx,  com- 
municates with  filaments  from  the  laryngeus  superior. 

The  Laryngeus  Inferior  has  branches  connecting  it 
with  the  inferior  cervical  ganglion  of  the  sympathe- 
tic; the  cardiac  plexus;  and  the  pulmonary  plexus  of 
nerves. 

The  Nervus  Sympatheticus  is  also  on  the  back 
part  of  the  great  vessels  of  the  neck  close  to  the  verte- 
brae ; it  is  commonly  said  to  be  in  their  sheath ; this, 
however,  is  a loose,  if  not  an  inaccurate  style  of  speech, 
as  by  passing  a knife  handle  below  the  sheath  and  rais- 
ing it  up,  it  will  be  seen  that  the  sympathetic  is  uof  one 
of  its  contents;  but,  on  the  contrary,  that  it  is  fasten 


NERVES. 


47 


ed  somewhat  tightly  to  the  longus  colli,  and  the  conti- 
guous muscles,  by  cellular  membrane. 

The  sympathetic  nerve  arises  by  filaments  of  the 
pterygoid  and  of  the  sixth  nerve,  which  form  a net- 
work in  the  carotic  canal  around  the  artery ; a little 
above  or  below  the  termination  of  the  canal,  they  unite 
by  two  principal  trunks  to  form  one  nerve.  This  cord 
is  close  to  the  eighth  and  ninth  nerves  and  opposite  to 
the  second  cervical  vertebra,  it  swells  out  into  the  Su- 
perior Cervical  Ganglion ; it  then  descends,  and,  oppo- 
site to  the  space  between  the  fifth  and  the  sixth  cervi- 
cal vertebrse,  it  forms  the  Middle  Cervical  Ganglion, 
which  is  much  smaller  and  more  irregular  than  the  first. 
The  sympathetic  is  traced  with  some  difficulty  from 
this,  in  consequence  of  the  numerous  branches  coming 
from  it ; a trunk,  however,  may  be  found,  as  the  con- 
tinuation of  it,  which  passes  to  the  interval  between 
the  head  of  the  first  rib  and  the  transverse  process  of 
the  last  cervical  vertebra,  where  another  enlargement 
occurs,  denominated  Inferior  Cervical,  or  First  Thora- 
cic Ganglion. 

The  First  Ganglion  is  increased  by  filaments  from  the 
sub -occipital,  the  first,  second  and  third  cervical  nerves, 
and  the  eighth  and  ninth.  The  Second  Ganglion  re- 
ceives filaments  from  the  fourth,  fifth  and  sixth  cervi- 
cal nerves.  The  Third  Ganglion  receives  filaments 
from  the  sixth  and  seventh  cervical,  and  the  first  and 
second  dorsal  nerves.  From  these  ganglions  proceed  the 
cardiac  nerves. 


48 


OF  THE  HEAD  AND  NECK. 


The  Nervus  Phrenicus  isa  small,  straight, insulat- 
ed nerve  coming  principally  from  the  third  cervical, 
but  also  derived,  in  part,  by  filaments  from  the  second 
and  fourth.  It  is  found  on  the  humeral  side  of  the  great 
vessels  of  the  neck,  removed  a considerable  distance 
from  them  and  lying  upon  the  anterior  face  of  the  sca- 
lenus anticus  muscle.  It  descendsinto  the  thorax  between 
the  subclavian  artery  and  vein,  and  within  the  anterior 
end  of  the  first  rib. 

Each  of  the  Cervical  Nerves,  including  the  sub-occi- 
tal,  after  its  ganglion  is  formed  by  the  posterior  fascicu- 
lus of  the  spinal  marrow,  exists  as  a trunk  which  is  join- 
ed by  the  anterior  fasciculus  of  the  same.  This  com- 
mon ti’unk  gets  out  between  the  transverse  processes  of 
the  cervical  vertebrae,  and  is  immediately  divided  into  an 
anterior  and  a posterior  branch.  The  posterior  branches 
are  distributed  to  the  muscles  and  to  the  integuments 
which  lie  on  the  posterior  part  of  the  cervical  verte- 
brae, but  the  anterior  branches  are  variously  disposed 
of.  The  sub-occipital  and  the  three  first  cervical  nerves 
have  their  anterior  branches  going  principally  to  the 
muscles  which  arise  from  the  transverse  processes  of  the 
vertebrae,  and  to  the  skin  of  the  neck.  Each  of  these  an- 
terior branches  is  united  by  filaments  to  the  nerve  above 
and  below  it,  and  a sort  of  plexus  is  formed  which  lies 
over  the  levator  scapulae  muscle.  Filaments  are  also 
sent  from  the  anterior  branches  of  the  cervical  nerves 
which  join  with  the  spinal  accessory  nerve,  tlie  hypo- 


NERVES. 


49 


glossal,  the  portio  dura,  the  sympathetic,  and  the  phre- 
nic in  various  ways,  which  are  too  numerous  to  be  men- 
tioned here. 

The  Axillary  Plexus,  from  which  the  nerves  of 
the  upper  extremity  are  principally  derived,  arises 
from  the  anterior  branches  of  the  four  inferior  cervical 
nerves  and  of  the  first  dorsal.  These  branches  are  much 
larger  than  the  posterior,  and  emerge  between  the  an- 
terior and  the  middle  scalenus  muscle.  They  send  some 
very  small  filaments  to  the  lower  and  middle  cervical 
ganglions  of  the  sympathetic. 


F 


PART  I. 


CHAPTER  II. 


Section  I. 

Of  the  Encephalon  or  Brain,  and  Spincd  Marrcyic. 

The  best  way  to  get  at  the  Brain,  both  in  public  and 
private  dissection,  is  to  make  a cut  through  the  scalp 
across  the  top  of  the  head  from  ear  to  ear,  then  to 
turn  down  the  scalp  over  the  face,  and  behind  the  back 
of  the  neck.  The  scull  cap  may  be  separated  by  a 
saw  carried  only  through  the  external  table  just  above 
the  tips  of  the  ears,  and  about  an  inch  above  the  super- 
ciliary ridges.  With  the  aid  of  an  iron  wedge  and  a 
mallet  the  bone  is  afterwards  easily  broken  through 
and  separated  from  the  dura  mater.  Bichat  breaks  the 
scull  cap  to  pieces  with  a hammer  and  then  removes  it. 

The  medullary  mass  placed  within  the  ca%dty  of  the 
cranium  is  termed  in  common  language  Brain.  It  af- 
fords the  following  parts  for  separate  examination.  1 , 
The  Membranes.  2.  The  Cerebrum.  3.  The  Cere- 


BRAIN,  AND  SPINAL  MARROW.  51 

bellum.  4.  The  Pons  Varolii  and  the  Medulla  Ob- 
longata. 

I . The  membranes  are  three : The  Dura  Mater. 
Tunica  Arachnoidea,  and  Pia  Mater. 

The  Duka  Mater  lies  immediately  in  contact  with 
the  bones  of  the  cavity  of  the  cranium,  being  closely 
connected  to  them  by  blood-vessels  and  filaments  of 
fibres.  It  is  a white,  shining,  semitransparent  me%^ 
brane  consisting  of  two  layers,  the  internal  of  which 
forms  several  processes.  The  most  conspicuous  is  the 
Falx  Major,  which  arises  from  the  centre  of  the  ante- 
rior part  of  the  sphenoid  bone,  from  the  crista  galli  of 
the  SBthmoid,  from  under  the  whole  of  the  middle  line 
of  the  frontal  bone,  the  sagittal  suture,  and  superior 
part  of  the  occipital  bone  as  far  as  the  juncture  of 
the  limbs  of  its  cross.  It  is  narrow  before  and  broader 
behind,  where  it  joins  with  the  tentorium. 

The  next  process  is  the  Tentorium,  which  forms  an 
arch  slightly  convex  above,  and  crescentic  in  its  gene- 
ral figure.  It  is  connected  to  the  horizontal  limbs  of 
the  occipital  cross,  to  the  superior  ridge  of  the  petrous 
bones,  and  to  the  posterior  clinoid  apophysis  on  each 
side.  Immediately  under  the  centre  of  the  tentorium, 
and  running  towards  the  occipital  foramen,  is  the  Lesser 
Falx.  On  each  side  of  the  sella  turcica  is  a process  of 
dura  mater  forming  its  lateral  boundaries.  At  the  an- 
terior-edge  of  the  tentorium  is  the  Foramen  Ovale 


52 


OF  THE  HEAD  AND  NECK. 


through  which  the  cerebrum  and  cerebellum  unite  by 
their  crura. 

In  the  angle  formed  by  the  reflection  of  the  internal 
lamina  of  the  dura  mater  from  the  external,  are  some 
large  triangular  cavities  called  Sinuses.  The  first  is 
the  Superior  Longitudinal  Sinus,  which  commences  by 
a small  beginning  near  the  crista  galli.  It  enlarges  by 
a continual  accession  of  veins  from  the  pia  mater  and  ter- 
minates at  the  occipital  cross.  On  cutting  into  it,  we 
sgc  it  lined  by  a delicate  smooth  membrane ; — its  sides 
retained  together  by  many  little  tendinous  chords  call- 
ed the  Chordae  Willisii; — and  the  veins  of  the  pia  ma- 
ter running  into  it  obliquely  forwards,  so  as  to  produce 
the  elfects  of  valves.  In  this  sinus,  also  under  the  dura 
mater  near  the  top  of  tlie  brain  are  many  small  bodies 
of  various  sizes,  the  Glandulae  Pacchioni,  from  a line  or 
less  to  three  or  four  lines  in  diameter.  One  of  the  largest 
of  these  bodies,  on  each  side,  actually  protrudes  from 
the  surface  of  the  brain  through  the  dura  mater,  and 
makes  a deep  pit  into  the  parietal  bone,  near  the  sagit- 
tal suture. 

From  the  posterior  extremity  of  the  longitudinal 
sinus  proceeds  on  each  side  in  the  posterior  margin  of 
the  tentorium,  the  Lateral  Sinus,  terminating  in  the 
foramen  lacerum  posterius. 

At  the  inferior  edge  of  the  falx  major  between  its 
duplication,  is  the  Inferior  Longitudinal  Sinus.  And 
at  the  junction  of  the  falx  major  and  tentorium  is  the 
Fourth  sinus,  formed  by  the  inferior  longitudinal  sinus 


BRAIN  AND  SPINAL  MARROW. 


53 


and  a vessel  from  the  interior  of  the  brain  called  the 
Vena  Galeni.  It  joins  the  superior  longitudinal  sinus 
at  the  internal  occipital  protuberance  where  the  gene- 
ral meeting  of  the  vessels  is  called  Torcular  Hiero- 
phili. 

Around  the  pituitary  gland,  in  the  sella  turcica,  is 
the  Circular  Sinus  of  Ridley;  and  at  the  side  of  the 
sella  turcica  is  the  Cavernous  Sinus.  On  the  occiput 
and  about  the  petrous  , bone  there  are  several  smaller 
sinuses  which,  together  with  the  circular  and  cavernous, 
empty  into  the  lateral. 

The  Dura  Mater  is  supplied  with  nerves  from  the 
fifth  pair  which  are  traced  with  some  difficulty.  Its 
principal  artery  is  from  the  internal  maxillary,  and 
passes  through  the  foramen  spinale,  making  the  deep 
arborescent  indentations  in  the  parietal  bones.  There 
are  some  other  branches  derived  from  the  internal  caro- 
tid and  vertebral.  The  veins  accompany  the  arteries, 
and  do  not  discharge  into  the  sinuses. 

Within  the  Dura  Mater  and  covering  the  whole  ex- 
terior surface  of  the  pia  mater,  is  a delicate  transparent 
membrane  with  no  red  vessels  in  its  composition,  the 
Tunica  Arachnoidea.  If  forms  an  uniform  covering, 
not  dipping  into  the  convolutions  of  the  encephalon.  It 
may  be  seen  distinctly  on  the  superior  surface  of  the 
brain  like  a shining,  smooth  surface  to  the  Pia  Mater, 
but  cannot  readily  be  raised  up  from  it.  On  the  basis 
of  the  brain  it  is  a lamina  naturally  separating  itself 


54 


OF  THE  HEAD  AND  NECK. 


about  the  medulla  oblongata  and  the  contiguous  parts, 
from  the  membranes  between  which  it  is  placed.  The 
Dura  Mater  is  simply  in  contact,  but  does  not  adhere 
to  it ; some  anatomists,  however,  as  Bichat,  believe 
that  it  lines  the  internal  surface  of  the  Dura  Mater, 
having  the  same  reflections  as  a synovial  membrane.  It 
secretes  the  lubricating  fluid  which  facilitates  the  mo- 
tions of  the  brain. 

The  PiA  Mater  is  a tenderand  highly  vascular  mem- 
brane, lying  in  close  eontact  with  the  brain,  dipping 
into  its  convolutions  and  spread  over  the  surface  of  its 
ventricles  in  a manner  difficult  to  be  understood  with- 
out dissection.  It  is  much  thinner  and  more  delicate 
in  the  cavities  of  the  brain  than  exteriorly,  and  seems 
there  more  like  a vascular  net- work  than  a perfect  mem- 
brane. It  is  highly  useful  in  conducting  vessels  into 
the  substance  of  the  brain  by  being  so  extensively 
spread  over  its  surface,  and  by  dividing  them  minutely 
before  they  penetrate  it. 

Its  blood  vessels  are  exceedingly  numerous,  being  re- 
ceived from  the  vertebral  and  internal  carotid  arte- 
ries at  the  basis  of  the  cranium  in  the  manner  which 
will  be  explained  at  the  end  of  the  chapter.  Its  veins, 
are  all  inserted  into  the  sinuses  of  the  dura  mater,  and 
therefore  do  not  accompany  the  arteries. 

2.  The  Cerebrum  fills  by  far  the  greater  part  of 
the  carity  of  the  cranium,  and  extends  from  tlie  tento 


BRAIN  AND  SPINAL  MARROW. 


55 


rium  and  anterior  basis  of  the  cranium  to  the  vault.  It 
is  partially  divided  above  by  the  falx  major,  into  two 
equal  parts  called  Hemispheres,  and  below  we  see  that 
each  of  these  hemispheres  is  sub-divided  into  three 
lobes.  The  Anterior  Lobe  is  upon  the  orbitar  process 
of  the  frontal  bone;  the  Middle  Lobe  in  the  middle  fossa 
of  the  basis  of  the  cranium;  and  the  Posterior  Lobe 
upon  the  tentorium.  Between  the  anterior  and  middle 
lobes  there  is  a deep  indentation,  the  Fossa,  or  Fissura 
Magna  Sylvii ; formed  by  the  edge  of  the  little  wings 
of  the  sphenoid  bone,  which  prescribe  their  boundaries. 
The  middle  and  posterior  lobes  are  not  so  well  separated 
from  each  other. 

The  external  surface  of  the  cerebrum  is  arranged 
into  many  convolutions  which,  at  a little  distance,  give 
it  the  appearance  of  intestines.  The  pia  mater,  dip- 
ping down  to  the  bottom  of  them  keeps  their  opposite 
faces  in  contact.  If  a section  be  made  into  the  brain, 
it  will  be  seen  to  consist  of  matter  of  different  colours 
and  consistence.  The  external  matter,  varying  from  a 
line  to  three  or  four  in  depth,  is  the  Cineritious  or 
Cortical ; is  of  a yellowish  red  colour ; somewhat  less 
consistent  than  the  other;  and  covers  all  the  convolu- 
tions. Within  the  cortical  is  the  Medullary  Matter, 
which  is  of  a white  colour,  with  small  spots  or  dots  of 
red,  owing  to  the  blood-vessels. 

Proceeding  to  an  examination  of  the  interior  struc- 
ture, by  separating  the  hemispheres,  we  shall  see  that 
just  below  the  edge  of  the  falx  major  they  adhere  by 


56 


OF  THE  HEAD  AND  NECK. 


the  pia  mater  of  the  opposite  sides.  Dissect  this  ad- 
hesion through,  which  brings  into  view  a broad  expan- 
sion of  medullary  matter,  the  Corpus  Callosum,  extend- 
ing from  the  anterior  to  the  posterior  edge  of  the  falx, 
and  marked  in  its  centre  by  two  white  lines,  running 
longitudinally  and  slightly  curved  with  their  convexi- 
ties towards  each  other.  Between  these  lines  is  a fossa 
called  Raphe.  Other  lines  not  so  distinct  pass  laterally 
and  at  right  angles  to  the  first  two.  By  pulling  the 
hemisphere  still  more  from  its  fellow,  we  bring  into  view 
its  edge,  which  laps  over  the  corpus  callosum  and  is  se- 
parated from  it  by  a fossa  running  the  whole  length  of 
the  latter. 

The  hemispheres  above  the  corpus  callosum  must 
now  be  removed  by  a sharp  knife,  whereby  a view  is 
got  of  the  Centrum  Ovale  of  Vieussens,  and  also  of  the 
connexion  formed  between  the  hemispheres  by  the  Cor- 
pus Callosum.  The  centrum  ovale  is  properlv  speak- 
ing the  oval  nucleus  of  medullary  matter  which  is  left 
when  the  cortical  is  scraped  or  cut  away,  but  is  most 
commonly  described  as  the  oval  disk  which  is  formed  by 
the  aforesaid  section.  The  corpus  callosum  is  placed 
in  its  middle,  and  forms  the  great  medullary  commis- 
sure between  its  two  sides,  and,  also  the  roof  of  the 
lateral  ventricles. 

By  removing  the  corpus  callosum  the  Lateral  Ven- 
tricles, one  on  each  side,  are  brought  into  view.  They 
are  very  irregular  ca\uties  consisting  each  of  three  pi*o- 


BRAIN  AND  SPINAL  MARROW. 


57 


cesses  or  cornua,  and  extending  from  the  anterior  to  the 
posterior  portions  of  the  hemispheres.  In  the  anterior 
lohe  is  the  Anterior  Cornu  separated  only  hy  the  Sep- 
tum Lucidum  from  its  fellow.  In  the  middle  lobe  is  the 
Inferior  or  Middle  Cornu  passing  in  a winding  direc- 
tion downwards  and  forwards ; and  in  the  posterior  lobe 
is  the  Posterior  Cornu,  also  called  Digital  Cavity. 

In  the  anterior  cornu  of  the  lateral  ventricle  is  the 
Corpus  Striatum,  a long  convex  body,  broad  before  and 
coming  to  a point  behind ; it  is  cineritious  or  cortical 
externally  and  medullary  within;  when  scraped  the 
latter  looks  fibrous.  At  the  posterior  part  of  the  cor-^ 
pus  striatum  is  the  Thalamus  Nervi  Optici,  a large  con- 
vex body,  the  surface  of  which  is  medullary  and  the 
interior  cortical ; it  has  a node  on  its  upper  and  another 
on  its  posterior  side,  of  different  sizes  in  different  sub- 
jects. Between  the  thalamus  and  the  corpus  striatum 
is  a streak  of  medullary  matter  called  Taenia  Striata. 

In  the  posterior  cornu  of  the  lateral  ventricle  is  a 
rising  called  Hippocampus  Minor ; and  in  the  inferior 
cornu  is  a larger  rising  the  Hippocampus  Major,  pass- 
ing to  its  bottom  and  increasing  in  breadth  as  it  descends. 
Its  lower  end  puts  on  the  appearance  of  a claw,  being 
called,  from  that  cause,  Pes  Hippocampi. 

A considerable  part  of  the  Thalami  Nervorum  Opti- 
corum  is  concealed  by  the  Fornix,  a triangular  arched 
body  of  medullary  matter  narrow  before  and  broad  be- 
hind, and  extending  from  the  anterior  to  the  posterior 
extremities  of  the  thalami.  It  commences  forwards  by 

H 


58 


OF  THE  H^AD  AND  NECK. 

two  crura  very  much  curved,  with  their  concavity  back- 
wards, and  which  arise  deeply  from  the  sides  of  the 
thalami  near  their  union  with  the  corpora  striata.  These 
crura  come  afterwards  into  contact,  increase  much  in 
breadth,  conceal  the  thalami,  and  form  this  triangular 
body  which  posteriorly  is  lost  in  the  back  of  the  cor- 
pus callosum  and  the  hippocampi  majores.  The  angle 
formed  by  the  back  and  lateral  margins  is  elongated  and 
accompanies  the  hippocampus  major  for  some  distance, 
in  the  form  of  a thin  crus  which  is  easily  demonstrated 
by  raising  it  on  the  knife  handle.  This  crus  is  the 
Corpus  Fimbriatum,  or  Taenia  Hippocampi,  The  un- 
der surface  of  the  fornix  is  called  Lyra. 

The  Septum  Lucidum,  is  fixed  between  the  lateral 
ventricles,  at  their  fore  part ; is  connected  above  to  the 
corpus  callosum,  and  below  to  the  fornix.  It  consists  of 
two  laminae  with  a cavity  between  them  at  their  front, 
called  occasionally  the  fifth  ventricle.  To  get  a good 
view  of  the  septum  lucidum,  it  should  be  examined  as 
the  corpus  callosum  is  raised  up.  In  many  subjects, 
particularly  when  there  has  been  a small  dropsical  effu- 
sion into  the  ventricles,  the  septum  looks  like  a continu- 
ation of  the  middle  of  the  fornix,  a lamina  of  it  being 
contributed  by  the  internal  margin  of  each  crus. 

Under  the  fornix  and  lining  the  cavities  of  the  late- 
ral ventricles,  as  well  as  the  other  ventricles,  is  placed 
a very  delicate  reflection  of  pia  mater  with  many  ves- 
sels in  it,  but  so  very  thin  that  it  can  scarcely  be  rais- 
ed up  as  a perfect  membrane.  Tliis  membrane  gets 


BRAIN  AND  SPINAL  MARROW. 


59 


into  the  lateral  ventricles  from  the  fossa  of  Sylvius  and 
under  the  back  of  the  corpus  callosum.  Along  the  hip- 
pocampus major  and  the  exterior  margin  of  the  fornix^ 
on  each  side,  is  placed  a fold  of  it  quite  loose  and  float- 
ing, and  consisting  of  a great  congeries  of  small  veins 
and  arteries.  This  fold  is  the  Plexus  Choroides,  which 
becoming  smaller  anteriorly,  dips  under  the  anterior 
crus  of  the  fornix,  and  its  veins  unite  into  a large  trunk 
which  runs  under  the  fornix  to  terminate  posteriorly 
in  the  vena  Galeni.  That  portion  of  the  pia  mater 
lying  under  the  fornix  and  bounded  on  each  side  by 
the  plexus  choroides,  is  called  the  Velum  Interposi- 
tum. 

The  fornix  should  now  be  raised  with  the  velum  in- 
terpositum,  by  cutting  through  its  anterior  crura  and 
turning  it  backwards,  which  gives  a more  perfect  view 
of  the  thalami.  From  these  bodies  on  the  opposite 
sides  being  in  contact,  a kind  of  junction,  the  Commis- 
sura  Mollis  is  formed  by  their  convexities.  Anterior  to 
this  junction  is  a triangular  space  called  Vulva.  It  is 
here  that  the  lateral  ventricles  communicate,  under  the 
anterior  crura  of  the  fornix,  with  the  third  ventricle. 
The  communication  is  the  Foramen  of  Monro.  Be- 
hind tTbe  commissura  mollis  is  a similar  triangular  space, 
the  Anus.  The  Third  Ventricle  is  brought  fully  into 
view  by  separating  the  thalami,  and  we  shall  find  that 
it  is  formed  of  the  space  between  them.  At  its  lower 
front  part  is  an  open  way,  the  Iter  ad  Infundibulum, 
leading  to  the  basis  of  the  brain,  and  at  its  posterior 


60 


OF  THE  HEAD  AND  NECK. 


part  is  the  aqueduct  of  Sylvius,  or  the  Iter  e Tertio 
ad  Quartum  Ventriculum. 

The  Tubercula  Quadrigemina,  or  Nates  and  Testes, 
are  situated  at  the  posterior  part  of  the  thalami,  the  nates 
being  above.  They  are  each  about  three  or  four  lines  in 
diameter;  consist  of  medullary  and  cineritious  matter; 
and  constitute  a means  of  communication  between  the 
cerebrum  and  cerebellum  by  being  united  to  the  valve 
of  the  brain,  which  is  inserted  into  their  lower  part. 

The  Pineal  Gland,  a small  oval  cineritious  body,  is 
found  on  the  top  of  the  nates.  It  is  commonly  four 
lines  in  its  longest  diameter,  and  contains  a small  quan- 
tity of  calcareous  luattei',  feeling  and  looking  like  fine 
sand,  which  however,  is,  occasionally  collected  into 
one  or  more  irregular  masses  a line  in  diameter.  This 
sandy  matter  is  the  Acervulus  Cerebri.  The  pineal 
gland  is  situated  between  the  nates  and  the  back  of  the 
fornix,  being  closely  connected  with  the  under  surface 
of,  and  surrounded  by,  the  velum  interpositum,  so  that, 
most  frequently,  when  this  membrane  is  raised  along 
with  the  fornix,  the  pineal  gland  is  torn  from  its  place. 
If  we  are  careful  to  avoid  this  accident,  we  shall  find, 
passing  along  the  upper  edge  of  the  thalami,  on  each 
side,  above  the  commissura  mollis,  a medullary  streak 
the  Peduncle  of  the  pineal  gland,  which'goes  from  the 
latter  to  the  anterior  crus  of  the  fornix. 

At  the  anterior  part  of  the  third  ventricle,  just  below 
the  crura  fornicis,  and  seen  between  their  curvature 
where  they  diverge,  is  the  Commissui’a  Anterior,  a 


BRAIN  AND  SPINAL  MARROW. 


61 


medullary  line  near  the  corpus  striatum,  passing  from 
the  lower  anterior  part  of  one  thalamus,  to  the  other. 
At  the  back  part  of  the  third  ventricle,  just  under  the 
pineal  gland,  is  the  Commissura  Posterior  passing  in 
the  same  way  from  one  thalamus  to  the  other. 

The  Valve  of  the  Brain,  is  seen  by  cutting  off  the 
posterior  lobes  of  the  cerebrum,  removing  the  tentori- 
um, and  dissecting  away  the  pia  mater  just  behind  and 
below  the  tubercula  quadrigemina.  It  passes  up  as  a 
broad  lamina  of  medullary  matter  an  inch  wide,  from 
the  central  part  of  the  cerebellum  to  the  inferior  por- 
tion of  the  testes.  By  introducing  a probe  from  the  third 
ventricle  through  the  aqueduct  of  Sylvius,  it  will  be  seen 
that  this  valve  forms  the  roof  of  the  fourth  ventricle;  and 
that  it  is  thinner  in  its  middle  than  on  either  side. 

The  further  examination  of  the  Encephalon  should 
be  prosecuted  by  detaching  it  from  the  basis  of  the  cra- 
nium and  turning  it  out,  the  nerves  being  left  as  long 
as  possible,  and  the  spinal  marrow  also.  When  inver- 
ted it  has  the  following  parts  uppermost.  The  anterior 
and  the  middle  lobes  of  the  Cerebrum ; The  two  lobes 
of  the  Cerebellum ; The  Pons  Varolii  or  Tuber  Annu- 
lare ; and  the  Medulla  Oblongata. 

The  Cerebellum  is  remarkable  for  the  difference 
between  its  size  and  that  of  the  Cerebrum,  as  it  occu- 
pies only  the  space  between  the  tentorium  and  the 
posterior  fossse  of  the  basis  of  the  cranium.  It  is  dhi 


62 


OF  THE  HEAD  AND  NECK. 


ded  into  two  hemispheres  or  lobes  by  the  falx  minor. 
Though  covered  by  the  same  membranes,  its  appearance 
differs  from  that  of  the  cerebrum  in  consequence  of  its 
having  no  regular  convolutions.  In  their  place  is  sub- 
stituted longitudinal  fissures  separating  its  surface  into 
laminae,  and  passing  for  the  most  part  horizontally; 
they  penetrate  to  very  different  depths,  from  four  lines 
to  eight  or  more,  thereby  increasing  the  surface  for  the 
entrance  and  exit  of  the  vessels.  The  upper  surface 
of  the  cerebellum  is  slightly  convex  corresponding  with 
the  concavity  of  the  tentorium ; The  under  surface  has 
a double  convexity  corresponding  with  the  double  con- 
cavity in  the  inferior  part  of  the  occipital  bone.  The 
upper  central  part  of  it,  just  above  the  fourth  ventricle 
is  called  vermis;  and  is  the  fundamental  portion  of  Gall. 

When  the  cerebellum  is  cut  into,  its  substance  is  found 
to  be  firmer  than  that  of  the  cerebrum,  and  the  cor- 
tical matter  bears  apparently  a more  considerable  pro- 
portion to  the  other  than  it  does  in  the  cerebrum.  The 
medullary  matter  is  found  principally  in  its  centre,  and 
sends  off  processes  in  every  direction  into  the  cortical. 
From  this  circumstance  the  medullary  matter  has  an  ar- 
borescent outline  upon  all  vertical  sections  made  into  the 
cerebellum.  Hence  the  name  of  Arbor  Vitae,  which  is 
merely  expressive  of  this  arrangement  vithout  designa- 
ting any  particular  part  of  it.  But  if  horizontal  cuts 
be  made  the  arbor  vitae  resemblance  is  not  manifested, 
and  the  proportion  of  medullary  matter  appears  more 
oonsiderable.  The  two  Crura  of  the  cerebellum  one  on  a 


BRAIN  AND  SPINAL  MARROW. 


63 


side  pass  from  the  medullary  portion,  being  in  fact  a mere 
continuation  of  it,  and  separated  from  each  other  by  the 
fourth  ventricle.  They  are  inserted  into  the  posterior 
upper  part  of  the  Pons  Varolii. 

The  Pons  Varolii  is  between  the  anterior  part  of  the 
cerebellum  and  the  posterior  part  of  the  middle  lobes  of 
the  cerebrum.  It  is  nearly  spherical  on  its  inferior  sur- 
face, and  about  sixteen  lines  in  diameter ; is  divided  into 
two  halves  by  a middle  longitudinal  fissure  with  trans- 
verse ridges  passing  from  it  on  each  side.  It  is  formed 
of  the  crura  cerebri  and  cerebelli.  In  its  substance  is 
much  cortical  matter,  arranged  into  striae  running  in 
different  directions.  The  Crura  Cerebri  arise  from  the 
medulla  of  all  the  lobes,  make  their  first  appearance  at 
the  back  of  the  anterior,  and  between  the  middle  lobes ; 
their  internal  margins  touch ; they  pass  backward  to  be 
connected  with  the  anterior  superior  part  of  the  tuber 
and  are  lost  in  its  substance.  They  are  formed  of  a 
mixture  of  medullary  and  cineritious  matter ; the  latter 
predominates  in  one  part,  and  from  its  particular  colour 
is  called  Locus  Niger.  The  Pons  Varolii,  thus  constitu- 
ted by  the  blending  of  the  substance  of  the  four  crura, 
is  fixed  upon  the  posterior  part  of  the  body  of  the  sphe- 
noid bone  and  on  the  cuneiform  process  of  the  os  occi- 
pitis. 

The  Medulla  Oblongata  is  that  portion  of  ence 
phalic  substance  between  the  Pons  and  the  superior 


64 


OF  THE  HEAD  AND  NECK. 


margin  of  the  first  cervical  vertebra.  Arising  from 
the  back  of  the  former,  it  swells  considerably  almost 
immediately,  and  then  tapers  down  gradually  to  form 
the  commencement  of  the  spinal  marrow.  There  is  a 
circular  indentation  above  defining  its  boundaries  with 
the  Pons,  but  below  there  is  none.  A longitudinal 
fissure  on  its  fore  part  divides  it  equally.  On  each  side 
of  this  fissure  above,  is  an  oblong  eminence  called 
Corpus  Pyramidal e,  coming  to  a point  below,  and  dis- 
appearing gradually.  On  the  outer  side  of  that  again, 
and  separated  from  it  by  a fissure  on  the  side  of  the 
medulla  oblongata,  is  an  ovoidal  and  still  more  prominent 
convexity,  but  not  so  long,  called  Corpus  Olivare.  And 
on  the  outside  of  this  is  another  and  smaller  eminence, 
the  Corpus  Pyramidale  Laterale,  or  Corpus  Restiforme. 
The  Medulla  Oblongata  consists  of  medullary  matter 
externally,  and  cineritious  internally.  By  lifting  it  up 
from  the  cerebellum  and  dissecting  away  the  tunica 
arachnoidea  and  pia  mater,  a good  view  may  be  got  of 
the  Fourth  Ventricle  of  the  brain,  which  is  closed  be- 
low and  separated  from  the  spinal  canal  by  these  mem- 
branes. It  will  now  be  easy  to  understand  that  the 
parietes  of  the  fourth  venfricle  are  formed  by  the  valve 
of  Vieussens  and  by  the  cerebellum,  above  and  poste- 
riorly; by  the  pons  Varolii  anteriorly;  by  the  Medulla 
Oblongata  below ; and  by  the  Crura  Cerebelli  laterally. 
The  posterior  face  of  the  Medulla  is  marked  by  an 
arrangement  of  its  surface  corresponding  in  some  mea- 


BRAIN  AND  SPINAL  MARROW. 


65 


sure  vvilh  the  slit  and  nib  of  a writing  pen,  from  which 
it  has  the  name  of  Calamus  Scriptorius. 

Between  the  Crura  Cerebri  at  their  anterior  part  are 
two  small  round  bodies,  three  lines  thick,  in  contact 
with  each  other;  they  are  the  Corpora  Albicantia  or 
EminentisB  Mammillares.  They  are  placed  in  a cineriti- 
ous  substance,  the  Pons  Tarini,  forming  with  them  the 
floor  of  the  third  ventricle. 

The  Infundibulum  is  a flat  funnel-shaped  tube 
alluded  to  in  the  account  of  the  third  ventricle,  but 
best  seen  in  this  period  of  the  dissection.  It  is 
placed  just  before  the  corpora  albicantia,  and  passes 
from  the  third  ventricle  to  the  pituitary  gland,  having 
its  apex  in  contact  with  the  latter,  and  its  broad  part 
opening  into  the  ventricle.  It  is  generally  impervious 
at  its  apex.  It  is  cineritious  externally,  which  gives  it 
a red  cast,  and  medullary  internally. 

The  Glandula  Pituitaeia  occupies  the  sella  tur- 
cica, and  is  somewhat  spherical,  being  about  six  or 
seven  lines  in  diameter.  Its  structure  is  firm  and  re- 
sisting, formed  of  a tough  cineritious  matter  externally, 
and  of  a kind  of  medullary  internally.  It  is  almost 
concealed  by  a close  reflection  of  dura  mater  over  it. 

There  are  nine  pairs  of  nerves  going  from  the  basis  of 

I 


66 


OF  THE  HEAD  AND  NECK. 


the  brain,  and  named  numerically  by  beginning  in 
front.* 

The  1st  Pair,  the  Olfactory  (Nervi  Olfac- 
TORii,)  appropriated  to  the  nose,  arise  by  three  striae 
from  the  corpora  striata,  and  make  their  appearance 
on  the  back  and  inferior  part  of  the  anterior  lobes. 
Their  structure  is  soft  and  pulpy,  and  they  are  protect- 
ed from  the  weight  of  the  brain  by  being  deposited  in 
a triangular  groove  formed  by  a convolution.  They 
swell  out  into  bulbs  at  their  fore  part  on  the  sides  of  the 
the  crista  galli,  and  perforate  the  cribriform  plate  of 
the  (Ethmoid  bone  by  numerous  filaments.  They  get  a 
coat  from  the  dura  mater  which  gives  them  great 
strength,  and  are  then  distributed  as  mentioned  in  the 
account  of  the  nose. 


The  2nd  Pair,  the  Optic  Nerves  (Nervi  Optici,) 
are  of  considerable  magnitude,  and  differ  somewhat  in 
their  texture  from  the  other  nerves  in  consequence  of 
having  a general  investment  of  pia  mater  before  it  sur- 
rounds their  particular  fasciculi;  and  also  from  hav- 
ing more  medullary  matter  in  them.  They  arise  from 
the  posterior  parts  of  the  thalami  and  make  their  appear- 
ance between  the  middle  lobes  and  the  crura  cerebri. 
There  is  a very  close  intertexture  of  the  nerves  of  the 


* This  is  the  most  usual  classification  of  the  nerves  but  is  ob- 
jectionable in  many  respects.  (See  Descriptive  Anatomy.) 


BRAIN  AND  SPINAL  MARROW. 


67 


opposite  sides  just  before  the  infundibulum,  so  that  it 
is  a question  whether  they  decussate  each  other,  or  sim- 
ply unite.  Being  the  nerves  of  vision,  they  pass  to  the 
ball  of  the  eye,  through  the  foramina  optica  and  are  ex- 
panded into  the  retina. 

The  3rd  Pair,  (Motores  Oculorum,)  arise  from 
the  inner  margins  of  the  crura  cerebri  near  the  pons  va- 
rolii  by  several  filaments.  They  pass  outwards  and  pene- 
trate the  dura  mater  near  the  posterior  clinoid  process 
and  traversing  the  upper  part  of  the  cavernous  sinus 
they  get  into  the  orbits  through  the  foramina  lacera. 
They  are  distributed  to  the  muscles  of  the  eye,  except 
the  obliquus  superior  and  rectus  externus,  and  contri- 
bute to  the  ophthalmic  ganglion. 

The  4th  Pair,  (Trochleares.  ) Each  arises  by  two 
filaments  which  quickly  unite,  from  the  valve  of  Vieus- 
sens  just  below  the  tubercula  quadrigemina.  It  is  not 
larger  than  a common  semng  thread,  and  makes  its  ap- 
pearance at  the  anterior  lateral  margin  of  the  pons 
varolii.  It  penetrates  the  edge  of  the  tentorium  not  far 
from  the  entrance  of  the  third  nerve,  and  running  in 
an  investment  of  dura  mater  through  the  cavernous 
sinus  at'^the  outer  side  of  this  nerve,  it  afterwards 
crosses  it  above,  and  getting  into  the  orbit  through  the 
foramen  laceriun,  is  appropriated  to  the  trochlearis 
muscle. 


68 


OF  THE  HEAD  AND  NECK. 


The  5th  Pair,  (Trigemini,)  are  the  largest  of  all. 
Each  arises  by  two  or  three  portions,  the  anterior  being 
smallest,  from  the  side  of  the  tuber  annulare  just  where 
it  is  blended  with  the  crus  cerebelli.  Their  fibres  are 
collected  into  one  cord,  which  passes  into  a canal  of  the 
dura  mater,  lying  on  the  anterior  part  of  the  petrous 
bone.  They  are  not  connected  to  the  canal  except  at 
its  lowest  part,  where  they  receive  a coat  from  it.  The 
nerve  is  then  expanded  like  a fan,  into  seventy  or  eighty 
filaments.  At  the  circumference  of  the  latter  is  a 
brownish  substance  the  ganglion  of  Gasser,  from  the  con- 
vexity of  which  pass  off  three  great  divisions,  named 
from  their  appropriations ; the  Ophthalmic  nerve  which 
goes  out  of  the  cranium  at  the  foramen  lacerum  of  the 
orbit;  the  Superior  Maxillary,  at  the  foramen  rotun- 
dum;  and  the  Inferior  Maxillary,  at  the  foramen  ovale. 

The  6th  Pair,  (Motores  Externi.)  Each  nerve 
arises  from  the  commencement  of  the  medulla  oblongata 
between  the  tuber  annulare  and  corpus  pyramidale.  It 
passes  forward  through  the  dura  mater,  in  a canal,  of 
the  cavernous  sinus,  on  the  inside  of  the  fifth  nerve, 
and  lying  between  this  nerve  and  the  carotid  artery,  it 
detaches  one  or  more  filaments  to  form  the  commence- 
ment of  the  sympathetic  nerve,  and  which  accompanies 
the  carotid  artery  through  the  carotid  canal  to  the  neck. 
The  trunk  of  the  motor  externus  then  gets  into  the  orbit 
through  the  foramen  lacerum  and  is  appropriated  to  the 
rectus  externus  muscle  of  the  eye. 


BRAIN  AND  SPINAL  MARROW. 


69 


The  7th  Pair,  is  composed  of  two  nerves,  the  Portio 
Mollis  and  the  Portio  Dura.  The  first  arises  from 
the  posterior  face  of  the  medulla  oblongata,  where  it 
forms  the  fourth  ventricle,  being  separated  from  its  fellow 
of  the  opposite  side  by  the  slit  of  the  calamus  scriptorius. 
The  second,  or  portio  dura,  arises  from  the  place  of 
junction  of  the  pons,  medulla  oblongata,  and  crus  ce- 
rebelli.,  A third  nerve  which,  at  a little  distance,  joins 
the  portio  dura,  and  is  a mere  fibril  called  Portio  Me- 
dia, arises  near  the  latter.  The  seventh  nerve,  thus 
constituted  of  a hard  and  of  a pulpy  portion,  dips  into 
the  meatus  auditorius  internus.  The  mollis  goes  to  the 
ear  and  is  spent  upon  the  labyrinth ; the  dura,  passing 
along  the  aqueduct  of  Fallopius,  gets  out  at  the  stylo- 
mastoid hole  and  goes  to  the  face. 

The  8th  Pair,  consists  of  three  portions  having  diffe- 
rent destinations:  The  Glosso-Pharyngeal ; the  Par  Va- 
guin or  Pneumo-gastric ; and  the  Spinal  Accessory  nerve 
of  Willis.  The  two  first  arise  near  each  other  from  the 
side  of  the  Medulla  Oblongata,  behind  the  Corpora  Oli- 
varia,  at  the  Corpora  Pyramidalia  Lateralia.  The  Clos- 
so-Pharyngeal  is  before  the  other,  and  consists  of  one 
cord.  The  Par  Vaguin  is  composed  of  several  fasci- 
culi having  a flattened  appearance,  which  afterwards 
unite  together.  The  Spinal  Accessory  has  a remark- 
able origin  from  the  Medulla  Spinalis,  occasionally  as 
low  down  as  the  seventh  cervical  nerve,  between  the 
anterior  and  posterior  fasciculi.  Its  fibres  successively 


70 


OF  THE  HEAD  AND  NECK. 


form  a round  trunk,  which  passing  up  the  spinal  canal  and 
then  into  the  cavity  of  the  cranium  through  the  foramen 
magnum,  is  associated  with  the  nerves  just  mentioned; 
it  is  assisted  also  by  contributions  from  the  side  of  the 
Medulla  Oblongata.  The  eighth  pair  passes  out  of  the 
cranium  at  the  posterior  foramen  lacerum,  anterior  to 
the  internal  jugular  vein,  and  separated  from  it  by  a 
spine  of  bone  as  well  as  by  a process  of  dura  mater. 
The  distinction  of  the  nerves  from  each  other  is  also 
kept  up  here,  by  processes  of  dura  mater  between 
them.  They  adhere  on  the  outside  of  the  cranium 
and  then  part  for  their  different  destinations  ; the 
Glosso-pharyngeal  for  the  tongue  and  pharynx,  the 
Par  Vagum  for  the  lungs  and  stomach,  and  the  Spi- 
nal Accessory  for  the  muscles  and  integuments  of  the 
neck. 

The  9th  Pair,  (Linguales.)  Each  nerve  arises 
from  the  side  of  the  medulla  oblongata  at  the  groove 
between  the  corpus  pyramidale  and  olivare,  by  three 
or  four  fasciculi.  These  fasciculi  unite  into  a trunk, 
which  gets  from  the  cranium  through  the  anterior 
condyloid  foramen,  and  is  distributed  to  the  tongue. 


BRAIN  AND  SPINAL  MARROW. 


71 


Of  the  Medulla  Spinalis. 

This  is  a continuation  of  the  medulla  oblongata,  con- 
tained in  the  vertebral  canal ; passes  down  as  far  as  the 
first  or  second  vertebra  of  the  loins;  and  there  ter- 
minates in  a eonical  point.  It  has  the  same  number  of 
membranes  with  the  Brain;  to  wit,  the  Dura  Mater, 
Tunica  Arachnoidea  and  Pia  Mater. 

The  Dura  Mater  resembles  very  mucli  the  same 
membrane  of  the  brain  except  that  it  has  more  elasti- 
city. It  does  not  adhere  closely  to  the  bone,  but  lies 
loosely  enveloping  the  spinal  marrow  and  nerves,  until 
it  touches  the  foramina  through  which  the  latter  pass 
out.  The  spinal  cavity  is  lined  its  whole  length  by  a 
ligamentous  membrane  which  strengthens  the  articula- 
tions of  the  vertebrae,  being  in  close  contact  with  them. 
Between  this  membrane  and  the  dura  mater  is  inter- 
posed a soft,  watery  and  vascular  fat,  which  forms  a sort 
of  bed  for  the  dura  mater  and  fills  up  many  of  the  in- 
equalities between  the  two  membranes.  At  the  egress 
of  the  dura  mater  from  the  cranium  just  around  the 
foramen  magnum,  it  adheres  closely  to  the  ligamentous 
lining. 

The  Pia  Mater  is  in  close  union  with  the  Medulla 
Spinalis,  and  is  commonly  found  with  its  veins  inject- 
ed after  the  same  way,  with  the  pia  mater  of  the  brain ; 
it  is,  however,  not  so  vascular. 


7% 


OF  THE  HEAD  AND  NECK. 


The  Tunica  Arachnoidealies  loosely  between  the  dura 
and  the  pia  mater,  preserving  a character  of  extreme 
tenuity  and  transparency;  it  may  be  elevated  any  where 
with  a pair  of  forceps ; continues  downwards  to  the  end 
of  the  spinal  cavity,  and  connects  the  fasciculi  of  nerves 
together. 

On  each  side  of  the  spinal  marrow  running  between 
the  anterior  and  posterior  fasciculi  of  nerves,  is  a 
narrow  semitransparent  band,  called  Ligamentum  Den- 
ticulatum,  fixed  beneath  the  tunica  arachiioidea,  and 
connected  to  the  pia  mater  by  cellular  substance.  It 
is  first  observed  arising  at  the  occipital  foramen;  it 
then  descends  between  the  lateral  fasciculi  of  nerves, 
being  united  to  the  pia  mater  by  its  internal  edge. 
As  the  ligament  passes  between  the^ anterior  and  poste- 
rior fasciculi  of  nerves,  it  detaches  little  round  tooth-like 
processes,  fixed  to  the  inner  surface  of  the  dura  mater, 
and  carrying  the  tunica  arachnoidea  along  with  them. 
From  these  processes  it  derives  its  name. 

The  Medulla  Spinalis  from  being  a continuation  of  the 
medulla  oblongata,  like  it  consists  of  two  kinds  of  mat- 
ter, cortical  and  medullary.  The  latter  is  placed  ex- 
ternally. The  medulla  spinalis  has  anteriorly  and  pos- 
teriorly a fissure  penetrating  almost  to  its  centre  and  ex- 
tended its  whole  length,  which  divides  it  into  two 
equal  parts.  These  halves  are  again  di\dded  each  into 
anterior  and  posterior  portions  by  a long  lateral  fissui’e 
which  is  not  so  deep  or  long  as  the  other.  These  seve-  . 
ral  divisions  of  the  spinal  maiTOW  being  connected  by 


BRAIN  AND  SPINAL  MARROW. 


4 0 

the  internal  cineritious  matter,  when  a horizontal  cut  is 
made,  the  latter  puts  on  a crucial  appearance. 

From  the  anterior  and  posterior  sections  of  the  spi- 
nal marrow  flat  fasciculi  of  nerves  proceed,  which  pene- 
trate the  dura  mater  separately  and  derive  a coat  from 
it.  This  coat  exists  for  some  distance  as  a sheath, 
united  to  the  nerve  by  loose  cellular  substance,  but  is 
closely  fixed  to  it  near  the  intervertebral  foramen.  The 
posterior  fasciculus,  at  this  place,  forms  a ganglion 
which  sends  out  a nerve  at  its  fore  part;  this  nerve, 
just  at  its  origin,  is  united  to  the  anterior  fasciculus, 
and  thus  forms  the  commencement  of  the  spinal  nerve. 
As  soon  as  the  spinal  nerve  clears  the  foramen  between 
the  bones,  it  sends  branches  backwards  to  the  muscles  of 
the  spine,  others  forwards  to  join  the  sympathetic,  and 
the  middle  trunk  goes  according  to  the  part  of  the  body 
to  be  supplied. 

There  are  thirty  pairs  of  spinal  nerves ; seven  to  the 
neck,  twelve  to  the  back,  five  to  the  loins,  five  to  the 
sacrum,  and  one  which  passes  between  the  occiput  and 
first  vertebra  called  Sub-occipital.  The  nerves  of  the 
neck,  from  their  origin  to  the  intervertebral  holes,  are 
short  and  nearly  horizontal ; those  of  the  back  pass  ob- 
liquely downwards,  increasing  in  obliquity  as  they  de- 
scend. The  lumbar  and  sacral  nerves  are  extremely 
oblique,  the  lowest  being  almost  vertical ; they  arise 
very  much  in  a cluster  close  to  each  other,  and  form, 
while  still  within  the  dura  mater,  the  Cauda  Equina. 


74 


OF  THE  HEAD  AND  NECK 


Of  the  Blood  Vessels  of  the  Brain  and  Spinal 
MarroiO. 

The  brain  is  supplied  by  the  Internal  Carotids  and 
the  Vertebral  Arteries.  The  former,  passing  in  a very 
tortuous  manner  through  the  canal  in  the  temporal 
bones,  appear  in  the  cavernous  sinus  at  the  sides  of  the 
anterior  clinoid  processes.  They  there  send  off,  each 
anteriorly,  the  ophthalmic  artery  through  the  optic 
foramen,  and,  in  a short  space  afterwards,  the  Arte- 
ria  Communicans,  a branch  which  goes  backwards,  to 
join  the  posterior  artery  of  the  cerebrum ; the  main 
trunk  is  continued  into  the  fossa  of  Sylvius,  and  forms 
the  Arteria  Media  Cerebri,  and  from  this  is  sent  off  the 
Arteria  Anterior  which  supplies  the  anterior  lobe  of  the 
brain  and  the  corpus  callosum.  The  arteria  anterior  com- 
municates by  a short  transverse  branch  with  its  fellow. 

The  Vertebral  Artei-ies  come  up  through  the  forameu 
magnum  and  unite  with  each  other  at  the  posterior 
part  of  the  pons  varolii,  to  form  the  basilar  arterjC 

The  Basilar  artery  divides  anteriorly  into  two 
branches  which  run  to  the  posterior  lobes  of  the  brain : 
they  constitute  the  Arterise  Posteriores  Cerebri.  From 
the  basilar  near  the  vertebrals,  arises,  on  each  side,  a 


BRAIN  AND  SPINAL  MARROW. 


75 


trunk,  the  Arteria  Inferior  Cerebelli ; and  from  its  an- 
terior part  the  Arteria  Superior  Cerebelli.  The  cir- 
cle of  Willis  is  formed  by  the  anterior  bifurcation  of  the 
basilar,  connected  to  the  internal  carotids  by  the  Arte* 
riae  Communicantes. 

The  veins  of  the  brain  have  been  mentioned  as  all 
emptying  into  the  sinuses  of  the  dura  mater. 

The  arteries  of  the  spinal  marrow  are  derived  from 
the  vertebrals,  intercostals,  and  arteries  of  the  neck. 
The  veins  accompany  the  arteries  forming  sinuses  on  the 
outside  of  the  dura  mater,  one  on  each  side,  which 
empties  into  the  occipital  and  lateral  sinus,  anasto^ 
mosing,  however,  very  freely  with  a plexus  of  veins 
which  surrounds  the  spinal  column. 


Section  II. 

Of  the  Jhiatomy  of  the  Brain  and  Spinal  Marrcrw, 
according  to  Gall  and  Spurzheim. 

I HAVE  thought  proper  to  add  this  section  on  account 
of  the  interest  felt  in  Philadelphia,  for  the  peculiar 
tenets  of  these  gentlemen,  and  because  I am  persuaded 


76 


OF  THE  HEAD  AND  NECK. 


that  th air’s  is  a very  improved  and  simplified  mode  of 
studying  the  anatomy  of  the  brain,  and  of  the  nervous 
system.  Whatever  may  be  the  ultimate  fate  of  their 
physiological  opinions,  it  ought  to  have  no  influence  on 
their  anatomical  observations,  as  the  two  subjects  are  in 
their  nature  distinct.  One  is  an  obvious  matter  of  fact, 
and,  for  the  most  part,  as  susceptible  of  demonstration 
as  the  contents  of  the  thorax ; the  other  rests  on  a more 
uncertain  foundation,  is  therefore  liable  to  error,  and 
should  not  be  considered  as  having  passed  its  period  of 
infancy,  and  the  ordeal  of  public  criticism. 

The -brain  and  spinal  marrow,  these  gentlemen  say, 
consist  of  two  kinds  of  substance,  cineritious  and  fibrous. 
The  first  is  found  abundantly  on  the  surface  of  the 
brain,  within  its  substance  at  particular  places,  and  dif- 
fused through  the  spinal  marrow.  Its  consistence  is 
pulpy  and  gelatinous,  varying  in  degree  in  different 
subjects,  and  of  a yellowish-red  colour  for  the  most 
part.  It  is  exti^emely  vascular,  in  consequence  of  which, 
some  anatomists  have  considered  it  to  consist  entirely 
of  blood-vessels,  but  Albinus  and  Soemmering  have 
both  proved  by  injections,  that  there  is  some  other 
substance  which  is  probably  secreted  by  them.  This 
substance  is  the  matrix  or  soil  of  the  nervous  fibres 
constituting  the  other  part  of  the  brain. 

A very  general  error  has  prevailed  in  regard  to 
what  is  called  the  medullary  portion  of  the  brain ; some 
consider  it  to  be  solid,  others  that  it  consists  of  hollow 
tubes,  some  that  it  has  no  vessels,  others  that  it  consist^ 


BRAIN  AND  SPINAL  MARROW. 


77 


entirely  of  them.  The  fact  is  that  it  is  fibrous,  whicli 
may  be  demonstrated  by  scraping  it  from  the  centre  to 
the  circumference  in  the  direction  of  its  fibres,  by  boil- 
ing its  convolutions  in  oil,  or  macerating  them  in  nitric 
or  muriatic  acid  diluted  with  alcohol.  For  these  reasons 
Messrs.  Gall  and  Spurzheim  reject  the  term  Medul- 
lary as  communicating  a false  idea,  and  call  it  the  Ner- 
vous Mass. 

The  Spinal  Marrow  in  worms  and  caterpillars, 
consists  of  a series  of  ganglions  united  to  each  other  by 
nervous  branches,  giving  it  the  form  of  a chord  with 
small  tubercles  of  various  shapes  and  sizes.  For  every 
superficial  ring  or  segment  of  these  animals,  there  is 
one  of  these  knots  or  ganglia  for  the  origin  of  nerves, 
and  the  size  and  number  of  the  nerves  emanating  from 
one  of  these  ganglia,  mil  always  be  in  proportion  to 
the  size  of  the  ganglion  itself.  In  fishes,  amphibia, 
and  birds  the  same  arrangement  prevails,  only  in  not 
so  distinct  a shape,  the  ganglia  being  nearer  to  each 
other,  and  with  the  uniting  bands  forming  a chord  of 
more  equal  size,  swollen ‘however  where  large  nerves 
go  off.  The  same  knotted  conditidn  is  observed  in  the 
mammalia  and  in  man,  but  not  so  evidently  in  the  lat- 
ter; one  may,  however,  be  convinced  of  it  by  removing 
the  spinal  marrow,  detaching  the  tunica  arachnoidea, 
and  observing  the  profile  between  the  eye  and  the 
light.  The  outline  is  every  where  more  or  less  wav- 
ing, corresponding  vith  the  origins  of  the  nerves,  the 


78 


OF  THE  HEAD  AND  NECK. 


largest  swellings  being  where  the  nerves  of  the  extre- 
mities go  olf;  which  are  the  largest  nerves  of  the  me- 
dulla spinalis.  The  spinal  marrow,  for  these  reasons, 
is  enlarged  from  the  third  vertebra  of  the  neck  to  the 
first  dorsal;  it  is  then  gradually  diminished  to  the  tenth 
dorsal;  it  afterwards  enlarges  to  the  first  lumbar  verte- 
bra, and  forms  an  elongated  point  where  it  terminates. 

In  the  medulla  spinalis  are  two  fissures  going  in  a 
vertical  direction,  one  in  the  middle  before,  and  the 
other  in  the  middle  behind,  which  divide  it  into  two 
equal  parts  or  halves;  the  first  is  wider  and  more  visi- 
ble, the  second  is  deeper.  There  are  no  lateral  verti- 
cal fissures,  as  some  anatomists  assert.  At  the  bottom 
of  the  anterior  fissure  the  two  halves  of  the  spinal  mar- 
row are  united  by  transverse  fibres  which  pass  from 
side  to  side,  forming  a layer,  and  at  the  bottom  of  the 
posterior  fissure  there  is  also  a corresponding  layer  of 
fibres  uniting  the  two  halves,  but  passing  longitudinally. 

The  medulla  spinalis  is  medullary  or  fibrous  exter- 
nally, and  eineritious  or  cortical  within.  The  cineri- 
tious  substance  forms  a distinct  arch  in  each  half,  which 
has  its  concavity  laterally,  its  two  extremities  will  of 
course  be  before  and  behind.  The  fasciculi  of  nervous 
fibres  follow  the  course  of  the  ends  of  these  arcs  from 
within  outwards,  some  coming  out  before,  and  others 
behind;  the  consequence  of  which  is,  that  there  are 
on  each  side  two  rows  of  nervous  fibres,  an  anterior  and 
a posterior.  The  posterior  fasciculi  are  the  larger,  fi’om 


BRAIN  AND  SPINAL  MARROW. 


79 


which  cause,  probably,  it  is  that  the  posterior  fissure 
penetrates  more  deeply. 

The  Encephalon  is  considered  by  all  anatomists  to 
consist  of  Cerebrum  or  Brain,  and  of  Cerebellum  or  lit- 
tle Brain,  each  of  which  is  formed  of  two  symmetrical 
halves  called  Hemispheres.  Besides  which  there  ex- 
ist the  Pons  Varolii  and  the  Medulla  Oblongata,  till 
lately  considered  as  emanations  from  the  Cerebrum  and 
the  Cerebellum. 

* 

On  each  side  of  the  Medulla  Oblongata  there  are 
three  protuberances ; the  most  anterior  is  the  Corpus 
Pyramidale,  just  behind  it  is  the  Corpus  Olivare,  and 
behind  it  again  is  the  Corpus  Restiforme ; these  pro- 
jections being  named  from  their  exterior  configuration. 
The  medulla  oblongata  consists  of  cortical  and  fibrous 
or  medullary  matter.  The  latter  is  eomposed  of  fas- 
eiculi  which  may  be  traced  into  the  brain  above,  and 
into  the  spinal  marrow  below.  Messrs.  Gall  and 
Spukzheim  consider  the  eerebral  mass  to  arise  from 
these  fasciculi  instead  of  the  latter  coming  from  the 
cerebral  mass,  as  is  most  conlmonly  taught  and  believed. 
The  corpora  pyramidalia,  like  the  other  eminences,  are 
fibrous,  and  their  fibres  arise  in  a peculiar  manner  from 
the  lower  part  of  the  medulla  objongata.  This  pecu- 
liarity consists  in  the  fibres  of  the  right  corpus  p}Ta- 
midale  arising  from  the  left  side  of  the  medulla  oblon- 
gata, and  the  fibres  of  the  left  corpus  pyi’amidale  aris 


80 


OF  THE  HEAD  AND  NECK. 


irig  from  the  right  side  of  the  medulla  oblongata.  These 
- fibres  decussate  each  other  an  inch  and  a quarter  be- 
low the  pons  varolii,  sometimes  in  single  bands,  but 
commonly  by  an  intertexture  of  three,  four,  or  five  fas- 
ciculi from  each  side.  When  traced,  their  origin  is 
found  to  be  in  the  cortical  substance  of  the  lower  part 
of  the  medulla  oblongata.  This  arrangement  is  readily 
seen  by  stripping  off  the  pia  mater  and  tunica  arachnoi- 
dea,  and  then  separating  the  two  sides  of  the  fissure  in 
front  of  the  medulla  oblongata. 

This  peculiarity  in  the  origin  of  the  pyramids  is  sup- 
posed to  explain  the  fact  of  blows  on  one  side  of  the 
head  paralysing  the  opposite  side  of  the  body,  as  the 
same  fibres  are  continued  from  the  origin  of  the  pyra- 
mids to  the  part  of  the  brain  which  is  injured  in  these 
cases.  In  regard  to  the  other  portions  of  the  medulla 
oblongata,  the  fibres  of  w^hich  they  consist  have  no 
such  arrangement,  but  arise  fairly  on  the  side  to  which 
they  belong ; are  continued  into  the  cerebral  mass  above 
and  communicate  with  the  medulla  spinalis  below. 

The  Cerebellum. 

The  Cerebellum  consists  of  two  lobes  or  hemispheres 
separated  in  part  by  a fissure,  which  makes  them  very 
distinguishable  from  each  other.  By  opening  this 
fissure  behind  we  get  a view  of  another  or  third  part 
of  the  cerebellum,  called  by  many  anatomists  Vermis. 


BRAIN  AND  SPINAL  MARROW. 


81 


but  by  G.  and  S.  the  Fundamental  Portion.  They  are 
induced  to  give  it  this  name  as  it  expresses  in  a measure 
a fact  of  some  importance,  viz.  that  it  always  exists  in 
animals  that  have  a cerebellum,  whereas,  the  lateral 
parts  or  lobes  do  not.  Fishes  and  reptiles  are  in  the 
latter  predicament,  but  all  warm-blooded  animals,  with 
man  at  their  head,  have  the  lobes. 

In  man  the  cerebellum  is  more  complicated  and  per- 
fect, nevertheless,  a constant  uniformity  is  observed  in 
all  animals  in  regard  to  the  origin  from  the  medulla  ob- 
longata. In  the  interior  of  the  medulla  oblongata  -on 
each  side,  within  the  corpus  restiforme,  an  accumulation 
of  cineritious  substance  is  observed  from  which  springs 
an  elementary  chord  of  fibrous  matter.  This  chord  in- 
creases as  it  ascends  towards  the  cerebellum,  and  near 
the  latter  is  covered  by  the  auditory  nerve  and  its  gang- 
lion. These  should  be  carefully  scraped  away;  we 
then  see  the  fasciculus  of  fibres  entering  into  the  inte- 
rior of  the  hemisphere  of  the  cerebellum.  Proceed- 
ing two  or  three  lines,  the  fibrous  chord  meets  with  a 
collection  of  cineritious  matter  of  an  oval  shape  with 
serrated  edges,  called  CorpXxs  Dentatum.  The  fibres 
become  so  blended  with  this  body,  that  it  is  impossible 
to  pursue  them  in  any  determinate  course.  The  cor- 
pus dentatum  is  considered  as  a ganglion  or  accumula- 
tion of  cineritious  substance,  for  the  purpose  of  giving 
origin  to  more  fibres  in  the  cerebellum.  Accordingly 
several  new  fasciculi  of  medullary  or  fibrous  matter 
arise  in  it,  and  ramify  in  different  directions  towards 


L 


82 


OF  THE  HEAD  AND  NECK. 


the  periphery  of  the  cerebellum.  Wherever  a large 
ramification  of  fibres  departs  from  it,  the  quantity  of 
cineritious  substance  about  its  root  is  increased,  hence 
results  the  fringed  or  serrated  margin.  That  the  cor- 
pus dentatum,  is  a pabulum  for  the  fibrous  structure  of 
the  cerebellum,  seems  proved  by  the  fact,  that  the 
greater  number  of  viviparous  animals  have  the  cerebel- 
lum proportionably  smaller  than  man,  and  in  them  the 
corpus  is  so  little  developed  that  they  are  said  by  some 
to  be  destitute  of  it. 

The  Corpus  Dentatum  detaches  inwardly  a large 
branch  which  contributes,  with  a corresponding  one 
from  the  other  side,  to  form  the  Vermis,  or  the  Fun- 
damental Portion  of  the  Cerebellum.  In  the  vermis, 
the  fibrous  or  medullary  matter  radiates  by  seven 
branches  towards  its  circumference,  their  extremities 
and  subdivisions  being  covered  by  cineritious  mat- 
ter. 

The  corpus  dentatum  also  sen'ds  off  other  branches 
which  go  upwards,  downwards,  and  outwards,  towards 
the  periphery  of  the  hemisjftiere ; expand  into  horizon- 
tal layers,  and  have  their  peripheral  extremities  cover- 
ed with  the  cineritious  substance.  Such  as  are  nearest 
to  the  middle  of  the  cerebellum  are  longest,  and  the 
others  gradually  decrease  in  length  as  they  are  nearer 
the  place  where  the  original  chord  entered  the  corpus 
dentatum.  If  the  cerebellum  be  cut  vertically  through 
the  middle  of  the  corpus  dentatum,  eleven  principal 


BRAIN  AND  SPINAL  MARROW. 


83 


branches  are  found  proceeding  from  it;  but  this  num- 
ber diminishes  if  the  eut  be  made  near  the  circumfer- 
ence of  the  cerebellum.  It  is  this  arborescent  arrange- 
ment which,  resembling  the  Thuya,  or  Tree  of  Life, 
gives  occasion  to  the  name  Arbor  Vitse. 

Horizontal  or  transverse  cuts  of  these  branches  or 
leaves  present  only  a white  substance ; therefore,  ana- 
tomists are  wrong  in  maintaining  that  the  quantity  of 
the  cineritious  mass  is  more  considerable  in  the  cerebel- 
lum than  in  the  brain.” 

Commissures  of  the  Cerebellum. 

A description  of  fibrous  matter  exists  in  the  cere- 
helium  which  cannot  be  traced,  either  to  the  primitive 
fasciculi  from  the  corpora  restiformia,  or  to  the  new 
fibres  derived  from  the  corpus  dentatum.  These  fibres 
come  from  the  cineritious  matter  on  the  surface  of  the 
cerebellum,  pass  in  various  directions  through  the  di- 
verging fibres;  but  always  so  as  to  converge  towards 
the  anterior  external  margin  of  the  cerebellum,  where 
they  form  a large  and  thick  layer  of  fibrous  matter.  The 
anterior  fibres  cross  in  front  of  the  tuber  annulare,  but 
the  middle  and  posterior  pass  transversally  through  it, 
getting  between  the  longitudinal  bands  of  the  tuber  an- 
nulare which  are  distributed  to  the  hemispheres  of  the 
cerebellum.  These  transverse  fibres,  from  the  opposite 
sides  of  the  cerebellum,  unite  with  their  congeners,  in  the 
middle  vertical  line  of  the  pons  varolii.  The  pons  varoliiis 


84 


OF  THE  HEAD  AND  NECK. 


therefore,  the  place  of  union  for  the  fibrous  structure 
of  the  two  hemispheres  of  the  cerebellum,  and  as  such 
is  called,  by  M M.  Gall  and  Spurzheim,  the  Great 
Commissure  of  the  Cerebellum. 

Considerable  light  is  thrown  upon  this  subject  by  com- 
parative anatomy,  for  this  great  commissure  has  its  di- 
mensions always  in  strict  proportion  to  the  development 
of  the  lateral  parts  or  hemispheres  of  the  cerebellum. 
In  the  mammalia  generally,  as  the  lateral  parts  of  the 
hemispheres  are  small,  the  tuber  annulare  is  small.  In 
fishes,  and  reptiles,  it  does  not  exist  at  all,  because  they 
have  no  hemispheres  to  the  cerebellum.  On  the  con- 
trary, in  man,  the  hemispheres  of  whose  cerebellum  are 
so  large,  the  tuber  annulare  is  remarkably  broad  and 
prominent,  so  much  so  as  to  conceal  the  origins  of  seve- 
ral nerves  which  are  visible  in  other  animals,  and,  there- 
fore, to  assume  fallaciously  the  appearance  of  giving 
origin  to  them. 

Although  such  animals  as  are  destitute  of  hemis- 
pheres are  without  the  great  commissure  of  the  cere- 
bellum, yet  as  they  all  have  the  fundamental  portion, 
so  they  have  a Lesser  Commissure  belonging  to  it.  This 
commissure  is  formed  of  the  fibres  which  come  from 
the  upper  and  lower  parts  of  the  fundamental  portion, 
and  join  each  other  in  constituting  the  ^ alvula  Cere- 
belli,  or  the  Valve  of  Vieussens,  which  runs  upwards 
and  forwards  to  join  the  Inferior  Tubercula  Quadrige- 


BRAIN  AND  SPINAL  MARROW. 


85 


mina  or  the  Testes.  This  primitive  commissure  of  the 
cerebellum  forms,  in  common  description,  the  roof  of 
the  fourth  ventricle. 

The  Cerebrum. 

The  cerebrum  is  derived  from  the  corpora  pyra- 
midalia  under  the  following  circumstances.  As  the 
pyramids  are  about  entering  the  pons  varolii,  they  con- 
tract so  as  to  give  the  appearance  of  a neck.  The  pons 
varolii  has  a considerable  quantity  of  cineritious  sub- 
stance in  it ; the  fibres  of  the  corpora  pyramidalia,  in 
passing  through,  are  divided  into  several  fasciculi  which 
derive  an  increment  from  the  cineritious  matter,  some 
of  the  fibres  being  disposed  in  layers  and  others  inter- 
woven with  transverse  cords  coming  from  the  cere- 
bellum. Besides  the  filaments  from  the  corpora  pyra- 
midalia, others  arise  from  the  posterior  part  of  tlte 
medulla  oblongata  and  from  the  corpora  olivaria  to  pene- 
trate into  the  pons  varolii.  The  several  fasciculi  thus 
formed  from  the  different  points  of  the  medulla  oblon- 
gata by  passing  through  the  cineritious  substance  of  the 
pons  varolii  are  so  reinforced  and  multiplied  that  on 
issuing  from  the  latter  they  form  the  pedunculi  or  crura 
of  the  brain.  And  as  in  man,  the  inferior  or  pyrami- 
dal fasciculi  receive  the  greatest  accession  of  new 
fibres ; they,  therefore,  form  two-thirds  of  these  crura. 

In  order  to  see  the  course  just  described  of  the  fibres 
of  the  medulla  oblongata,  remove  its  membranes  and 


86 


OF  THE  HEAD  AND  NECK. 


those  of  the  pons,  and  make  an  incision  one  line  deep 
through  the  front  of  the  pons  from  the  crus  of  the  cere- 
brum to  the  base  of  the  corpus  pyramidale  of  the  same 
side.  With  the  handle  of  a scalpel  introduced  to  the 
bottom  of  the  incision,  scrape  or  push  the  surface  of  the 
pons  towards  the  crus  of  the  cerebellum  on  the  one 
hand,  and  towards  the  middle  line  af  the  pons  on  the 
other.  We  thus  obtain  a distinct  sight  of  the  trans- 
verse medullary  fasciculi  constituting  the  anterior  super- 
ficial layer  of  the  pons  also  called  the  great  commissure 
of  the  cerebellum,  and  when  all  these  are  removed  we 
see  plainly  the  longitudinal  fibres  coming  from  the 
pyramidal  bodies ; by  scraping  still  deeper,  more  of 
the  fibrous  structure  of  the  tuber  annulare  is  brought 
into  view. 

The  anterior  and  external  fibres  of  the  crura  of  the 
cerebrum  are  derived  from  the  continuation  and  the 
successive  increase  of  the  primitive  pyramidal  bundles, 
or  the  corpora  pyramidalia.  The  incessant  reinforce- 
ment of  these  fibres  is  produced  by  their  meeting  con- 
tinually in  the  Tuber  Annulare  and  the  Crura  Cerebri 
with  cineritious  substance.  At  the  upper  extremity  of 
the  crus  where  the  optic  nerve  crosses  it,  the  corpus 
striatum,  a large  mass  of  cineritious  substance,  exists, 
and  with  which  blend  the  fibres  of  the  crus,  whence  an 
immense  number  of  new  fibres  is  generated  and  added 
to  the  course  of  the  others.  These  fibres,  shortly  after 
their  origin,  begin  to  diverge,  and  being  expanded  in 
several  directions  terminate  in  the  convolutions  of  the 


BRAIN  AND  SPINAL  MARROW. 


87 


anterior  and  middle  lobes  of  the  brain ; not  in  all  of  the 
convolutions  belonging  to  these  lobes>  but  in  the  inferior, 
anterior,  and  exterior.  In  this  way  the  original  fibres 
of  the  corpora  pyramidalia  may  be  traced  through  the 
medulla  oblongata,  tuber  annulare,  crura  cerebri,  and 
corpora  striata,  to  their  terminations. 

The  fibrous  fasciculi  on  the  posterior  and  external 
part  of  the  medulla  oblongata  formed  by  the  corpora 
olivaria,  and  a few  others  just  behind,  ascend  in  the 
same  manner  as  those  of  the  corpora  pyramidalia; 
through  the  transverse  fasciculi  of  the  pons  varolii 
which  come  from  the  cerebellum.  By  meeting  also 
with  cineritious  substance  they  are  multiplied,  but  less 
considerably  than  the  fasciculi  from  the  corpora  pyra- 
midalia. They  form  the  interior  and  posterior  part  of 
the  crura  cerebri  and  pass  through  the  thalami  nervo- 
rum opticorum.  The  thalamus  consisting  principally 
of  cineritious  substance,  through  which  the  fasciculus 
of  the  corpus  olivare  has  to  pass,  the  fasciculus  has  an 
accession  of  many  new  fibres.  M M.  Gall  and 
Spurzheim  reject  the  opinion  of  the  optic  nerve  aris- 
ing from  the  thalamus,  and  rather  consider  the  thala- 
mus as  one  of  the  ganglions  of  the  brain,  from  its  being 
appropriated  to  the  production  of  a great  number  of 
fine  fibres,  which  ascend  in  a diverging  direction,  and 
which  at  their  exit  from  the  superior  margin  of  this 
ganglion  form  large  fasciculi.  The  anterior  fasciculi 
of  the  thalamus  penetrate  the  corpus  striatum  where  it 
•forms  a part  of  the  lateral  ventricle,  and  receive  from 


88 


OF  THE  HEAD  AND  NECK. 


it  a considerable  accession  of  new  fibres.  All  the 
several  fasciculi  of  the  thalamus,  by  radiating  very 
widely,  are  finally  distributed  in  the  convolutions  of 
the  posterior  lobes  of  the  brain,  and  in  the  superior 
convolutions  of  the  anterior  and  the  middle  lobes. 

From  the  pyramidal  fasciculi  passing  through  the 
corpora  striata  and  being  there  multiplied,  and  from 
the  olivary  fasciculi  passing  through  the  thalami  and 
being  there  also  multiplied,  the  corpora  striata  and  the 
thalami  are  said  to  be  ganglions,  or  an  apparatus  of  in- 
crease where  many  new  fibres  arise  and  join  othei’s. 
By  such  arrangement  new  cerebral  fasciculi  are  added 
to  the  old  in  the  same  way  that  many  branches  might 
be  engrafted  upon  the  stock  of  a tree. 

Commissures  of  the  Cerebrum. 

The  Hemispheres  of  the  Brain  offer  the  same 
phenomena  as  the  cerebellum  in  regard  to  the  two 
orders  of  nervous  fibres.  The  fibrillse  which  come 
from  the  crura  cerebri  in  expanding  in  order  to  form 
the  duplicatures  or  convolutions  at  the  periphery  of  the 
hemispheres,  stop,  as  has  been  observed,  with  their 
points  in  the  cineritious  substance.  But  it  is  certain 
that  besides  these  fibres  there  may  be  demonstrated  in 
all  the  circumference  of  the  hemispheres  beyond  the 
tissue  on  which  rests  the  base  of  the  convolutions,  a 
particular  nervous  substance,  which  appeal’s  to  be  at 
first  spread  in  layers,  and  which  is  afterwards  united 


BRAIN  AND  SPINAL  MARROW. 


89 


into  filaments,  and  lastly  into  distinct  fasciculi.  These 
fasciculi  converge  or  incline  towards  the  interior  of  the 
brain  in  order  to  form  with  their  congeners  of  the  op- 
posite side,  a commissure  between  the  two  hemispheres. 
In  some  convolutions  of  the  part  folded  below  the  pos- 
terior lobe,  this  converging  mass  may  be  followed  in 
an  uninterrupted  bed  till  it  forms  distinct  J&laments. 
For  this  reason  it  is  that  we  presume  that  this  white 
and  soft  substance  to  be  met  with  in  all  the  convolutions, 
is  continued  every  where  in  the  same  manner  to  the 
commissures,  although  it  be  not  susceptible  of  distinct 
demonstration.” 

‘‘  As  these  fibres  converge,  and  as  they  have  in 
every  part  a different  course,  and  indeed  in  some  places 
one  altogether  different  from  the  diverging  fibres,  or 
such  as  come  from  the  base  of  the  brain,  particularly 
in  the  anterior  and  posterior  parts  of  it : As,  besides 
this,  they  are  separated  from  them,  and  much  softer 
and  more  white,  we  believed  ourselves  authorized  to 
consider  them  as  a particular  nervous  system.” 

The  Corpus  Callosum,  or  Great  Commissure,  is 
therefore,  derived  from  the  converging  or  returning 
fibres  of  the  hemispheres  of  the  cerebrum ; the  fibres 
from  the  opposite  sides  uniting  at  the  raphe.  The 
anterior  and  posterior  lobes  are  so  disposed,  that  their 
returning  fibres  do  not  cross  transversely,  but  in  a 
radiated  manner ; hence  the  great  commissure  is  shorter 
than  the  hemispheres,  as  it  occupies  only  their  middle 

M 


90 


OF  THE  HEAD  AND  NECK. 


part.  Also  as  these  fibres  are  eollected  very  much  in 
consequence  of  their  converging,  the  anteiior  and  pos- 
terior edges  of  the  corpus  callosum  are  thicker  than  its 
middle,  and  present  the  appearance  of  a fold  not  unlike 
that  of  the  pectoralis  major  at  the  arm-pit. 

The  CoMMissURA  Anterior  is  derived  from  the 
converging  fibres  of  the  front  convolutions  of  the  middle 
lobes.  These  fibres  pass  through  the  corpora  striata 
without  adhering  to  them,  and  present  on  both  sides 
of  the  brain  the  form  of  a bow  with  its  convexity  for- 
ward. 

The  CoMMissuRA  Posterior  is  derived  from  the 
posterior  convolutions  of  the  middle  lobes  of  the  brain, 
and  from  some  of  those  of  the  posterior  lobes.  It  also 
consists  of  converging  nervous  fibres,  which  are  lost  in 
the  posterior  duplicature  of  the  Commissura  Magna. 
It  forms,  at  its  junction  with  its  fellow,  a fiat  band  and 
not  a round  chord,  and  is  much  smaller  than  the  anteri- 
or commissure.  The  Middle  Commissure  of  the  cere- 
brum is  a mass  of  very  soft  and  delicate  transvei’se  fibres, 
going  from  one  thalamus  to  the  other,  in  the  space 
between  the  anterior  and  posterior  commissures.  These 
transverse  fibres  are  almost  always  torn,  upon  separat 
ing  the  hemispheres. 

Several  other  parts  of  the  cerebrum  are  considei’ed 
as  commissures  by  G.  and  S.,  or  consisting  of  converg- 
ing fibres,  as  the  T»nia  Striata,  the  Posterior  Crura  of 


BRAIN  AND  SPINAL  MARROW. 


91 


the  Fornix,  and  the  Lyra  or  under  surface  of  the  For- 
nix. They  do  not  consider  the  obliquity  of  the  course 
of  the  fibres  of  these  bodies,  an  objection  to  their 
being  commissures,  inasmuch  as  the  returning  filaments 
of  the  middle  parts  of  each  hemisphere,  are  the  only 
ones  which  have  a transverse  direction. 

The  Septum  Lucidum  is  also  a commissure  arising 
by  a fasciculus  of  fibres  sometimes  strongly  marked, 
from  the  most  internal  convolution,  at  the  anterior  ex- 
tremity of  the  middle  lobe,  on  each  side.  It  ascends,  in 
front  of  the  anterior  commissure,  above  the  junction  of 
the  optic  nerves,  and  is  spread  into  a delicate  membrane, 
forming  with  its  fellow  the  septum  of  the  lateral  ven- 
tricles. Between  the  two  laminae  composing  it,  is  a 
cavity  called  the  fifth  ventricle  of  the  Brain.  These 
laminae  are  extended  through  the  middle  of  the  great 
commissure,  and  assist  in  forming  the  raphe  by  means  of 
perpendicular  fibres,  the  direction  of  which  is  diverg- 
ing towards  the  convex  or  superior  part  of  the  great 
commissure. 

It  is  probable  that  all  the  nerves  of  animal  life  have 
those  commissures  and  at  any  rate  they  are  visible  in 
many  other  places.  For  example,  they  exist  in  the 
transverse  fibres  at  the  bottom  of  the  anterior  fissure  of 
the  spinal  marrow  and  of  the  medulla  oblongata,  in  the 
latter  of  which  we  must  take  care  not  to  confound  them 
with  the  decussation  of  the  pyramids.  And  besides 
this,  the  longitudinal  band  at  the  bottom  of  the  posterior 


92 


OF  THE  HEAD  AND  NECK. 


fissure,  extending  the  whole  length  of  the  spinal  mar- 
row, keeps  its  several  nerves  concatenated.  The  trans- 
verse band  behind  the  commissure  of  the  cerebellum 
in  mammiferous  animals,  the  junction  of  the  tubercula 
quadrigemina  and  the  transverse  band  at  the  origin  of 
the  fourth  pair  of  nerves  are  similar  unions  or  commis- 
sures. 

It  is  not  possible  to  say  with  propriety  that  these 
commissures  are  positive  unions  of  the  converging 
fibres,  from  the  corresponding  parts  on  each  side ; for 
a perpendicular  cut  through  the  middle  line  of  the 
corpus  callosum,  of  the  tuber  annulare,  and  the  middle 
of  the  spinal  marrow,  demonstrates  perpendicular 
strisB  accompanied  with  blood-vessels.  Possibly  the 
vertical  laminae  on  each  side  of  the  middle  line,  may 
form  a seam  by  juxtaposition;  but  it  is  more  proba- 
ble that  the  converging  fibres  are  continued  across 
these. 

Besides  the  commissures,  there  are  Transverse  Bands 
Complicationes  Transversse,)  which  should  be  attend- 
ed to.  Messrs.  G.  and  S.  consider  them  as  correspond- 
ing with  the  transverse  bands  at  the  joints  of  straw. 
They  say  that  at  every  point  of  considerable  increase 
there  is  one  of  them,  as  at  the  lower  end  of  the  Cor- 
pus Olivare,  in  the  middle  of  the  Crus  Cerebri,  at  tlie 
external  margin  of  the  optic  nerve  in  the  Crus  Cerebri, 
between  the  Thalamus  and  Corpus  Striatum,  at  the  ex- 
ternal margin  of  the  Corpus  Striatum. 


BRAIN  AND  SPINAL  MARROW. 


93 


The  Emuse^ttije  Mammilla  res  are  separated  in 
the  human  subject,  but  adhere  so  as  to  form  only  one 
body  in  other  mammalia.  Each  eminentia  contains  three 
cords,  two  internal  and  one  external.  The  external 
unites  with  the  transverse  band  under  the  optic  nerve 
in  the  crus  cerebri.  The  foremost  of  the  two  internal 
cords  unites  with  the  anterior  crus  of  the  fornix  of  the 
same  side,  and  the  other  sinking  into  the  interior  of  the 
thalamus,  unites  with  another  transverse  band.  They 
are  true  ganglions.  ^ 

The  Pineal  Gland  is  erroneously  named,  as  it  has 
nothing  of  a glandular  structure,  but  is  composed  of 
cineritious  and  medullary  substance.  Four  nervous 
threads  are  produced  in  it  which  go  to  contiguous 
parts,  two  on  each  side ; one  goes  along  the  superior 
internal  margin  of  the  thalamus,  and  ends  in  one  of 
the  transverse  fasciculi  found  in  the  divergent  fibres. 
The  second  goes  backwards  and  downwards,  and  ad- 
heres to  the  commissure  of  the  Tubercula  Quadri- 
gemina. 

“ The  Pituitary  Gland  is  a collection  of  cineri- 
tious substance,  placed  behind  the  junction  of  the  optic 
nerves.  It  is  obviously  traversed  by  white  filaments 
which  arise  in  it,  and  it  is  prolonged  into  the  Infundi- 
bulum.” 

The  Tubercula  Quadrigemina.  The  anterior 


94 


OF  THE  HEAD  AND  NECK.  J 

ones  or  the  nates,  are  evidently  ganglions  for  the  ori- 
gins of  the  optic  nerves,  (see  the  account  of  these 
j nerves.)  They  are  flattened  and  somewhat  cineritious 
I externally,  and  are  united  to  each  other  by  a strong 
* -and  broad  fasciculus,  considered  as  a commissure  of 
the  optic  nerves.  The  testes  are  of  a more  conical 
^|;  and  elevated  form,  the  medullary  matter  in  them  is 
I more  external,  and  they  have  also  a transverse  band 
which  unites  them.  The  use  of  the  testes  is  unknown, 
but  they  are  supposed  to  give  origin  to  the  olfactory 
nerves,  though  it  cannot  be  demonstrated. 

Of  the  Ventricles  and  Convolutions  of  the  Brain. 

It  has  been  stated  that  the  brain  has  two  ordei’s  of 
medullary  fibres,  the  one  called  diverging,  because 
they  have  their  rudiments  in  the  medulla  oblongata, 
and  are  so  spread  as  to  have  their  extremities  termi- 
nating near  the  periphery  of  the  brain,  in  the  cineri- 
tipus  substance  forming  it.  The  other  order  of  fibres 
is  called  converging,  because  they  pass  from  the  cir- 
cumference of  the  brain  to  the  interior  parts  or  mid- 
dle line,  and  constitute  the  Commissures.  These  con- 
verging  fibres  cross  the  diverging  at  various  angles, 
sometimes  obliquely,  sometimes  in  a rectangular  direc- 
tion. It  is  uncertainy^vhence  they  proceed,  whether 
they  are  derived  from  the  imperceptible  and  curved 
extremities  of  the  diverging  fibres  in  the  same  way  that 
the  veins  are  continuations  of  the  arteries,  or  who- 


BRAIN  AND  SPINAL  MARROW. 


95 


ther  they  are  a new  creation  in  the  cortical  circumfer- 
ence of  the  brain  where  they  have  their  primitive  radi- 
cles, in  a manner  Corresponding  with  the  origins  of  other 
nerves  in  the  dilferent  ganglions.  As  the  diverging 
fibres  or  mass  is  extended  in  every  direction  towards 
the  circumference  of  the  brain,  and  as  the  converging 
fibres  come  from  all  parts  of  the  same  circumference, 
and  form  large  layers  in  the  upper  portion  of  the  brain, 
as  for  instance  the  corpus  callosum,  it  results  that  be- 
tween the  two  orders  of  fibres  there  are  vacuities ; and 
these  are  called  the  ventricles  of  the  brain. 

The  Convolutions  of  the  Brain  have  generally  been 
considered  by  anatomists,  as  intended  merely  to  increase 
its  surface,  in  order  that  the  blood-vessels  of  the  pia 
mater  might  have  more  convenient  access  to  it.  This 
opinion  is  renounced  by  Messieurs  Gall  and  Spurz- 
HEiM  on  account  of  its  being  too  mechanical,  and  they 
think,  that  the  convolutions  are  the  result  of  a more 
important  and  finished  arrangement,  which  is  as  fol- 
lows. 

Immediately  after  the  diverging  fibres  decussate  the 
converging,  which  they  do  at  the  external  margins  of 
the  ventricles,  they  separate  from  each  other  and  are 
prolonged  into  the  convolutions,  forming  a fibrous  ex- 
pansion. These  fibres  are  not  all  of  the  same  length, 
for  some  stop  near  the  sides  of  the  ventricles  at  the  bases 
of  the  convolutions,  and  others  are  extended  to  the  sur- 
face of  the  brain.  By  such  arrangement  the  convolu- 


96 


OF  THE  HE  AH  AND  NECK. 


tions  are  also  of  different  depths.  Each  convolution 
consists  of  two  layers  of  the  diverging  fibrous  or  medul- 
lary matter,  which  are  symmetrical,  are  in  juxtaposi- 
tion, and  adhere  to  each  other  by  their  contiguous  sur- 
faces. Besides  this,  as  has  been  several  times  stated, 
each  convolution  has  its  covering  of  cineritious 
matter,  about  a line  or  a line  and  a half  deep.  The 
medullary  fibres  penetrate  somewhat  into  the  internal 
face  of  this  covering,  from  which  it  is  paler  and  more 
firm  than  the  exterior  surface.  The  fibrous  matter  be- 
ing successively  inserted  into  the  sides  of  the  cortical 
covering  of  the  convolutions,  its  quantity  of  course  is 
diminished  at  the  summit  of  tlie  convolution ; hence 
each  simple  convolution  is  wider  at  its  base  than  at  its 
summit.  Some  of  the  convolutions  however  reverse 
this  rule,  for  they  are  flattened  or  depressed  at  their 
summits,  like  a ridge  or  duplicature  of  cloth  ha\-ing  its 
top  pushed  a little  inwards.  The  convolutions  do  not 
all  stand  out  in  a radiated  direction  as  regards  the  cen- 
tre of  the  brain,  for  some  of  them  are  bent  either  to  one 
side  or  the  other. 

Each  convolution,  besides  being  formed  by  the  ends 
of  the  diverging  fibres  covered  with  cineritious  matter 
has,  in  its  structure,  nervous  fibres  more  minute  and 
soft  than  the  diverging  ones.  These  are  the  com- 
mencements of  the  converging  fibres,  and  can  be  seen 
only  in  the  convolutions  of  the  posterior  lobes  of  the 
brain;  the  inference,  however,  is  made  that  they  exist 
in  all  the  convolutions.  It  is  these  fibres  which  accu- 


BRAIN  AND  SPINAL  MARROW. 


97 


Ululate  at  their  decussation  with  the  diverging  ones,  or 
immediately  after,  into  the  large  fasciculi  which  form 
the  ventricles  and  the  commissures. 

If  we  separate  a convolution  from  the  brain  and  make 
a perpendicular  cut  across  it,  the  cut  surface  is  plain 
and  exhibits  no  mark  of  being  divisible  into  two  lami- 
nse.  Yet  it  does  consist  of  two  laminae  with  their  op- 
posite faces  in  contact,  and  agglutinated  in  all  proba- 
bility to  each  other  by  a loose  cellular  tissue.  This  fact 
is  proved  by  the  effects  of  hydrocephalus,  for  here  the 
water  acting  constantly  with  a distending  foi'ce,  sepa- 
rates the  two  laminae  of  fibrous  matter  and  sometimes 
effaces  the  appearance  of  convolution,  converting  it  into 
a membrane.  The  prolongations  or  convolutions  of  the 
cerebellum  are  formed  after  the  same  fashion,  except 
that  they  are  divided  into  branches  and  leaves  and 
are  smaller  than  those  of  the  brain. 

In  the  case  of  a woman  affected  with  hydrocephalus, 
Dr.  Gall  found  the  following  condition  of  the  brain. 
The  cerebral  mass  was  distended  into  a large  bladder,  by 
which  the  total  or  partial  disappearance  of  all  the  con- 
volutions had  been  produced.  In  places  where  they 
had  disappeared  entirely,  the  cineritious  substance  was 
of  almost  uniform  thickness.  All  the  interior  surface 
of  the  enlarged  ventricles  was  perfectly  white,  and,  in 
a majority  of  places,  not  only  the  nervous  fibres  were 
distinctly  seen,  but  the  blood-vessels  which  accompany 
them.  The  ventricles  contained  about  four  pints  of 


98 


OF  THE  HEAD  AND  NECK. 


clear  and  limpid  water.  The  fibrous  structure  and  the 
blood-vessels  had  no  where  been  impaired.  This 
woman  died  at  the  age  of  fifty-four  of  an  inflammation 
of  the  bowels,  but  from  her  earliest  infancy  she  had 
been  afflicted  with  hydrocephalus.  She  was  not  very 
thin,  and  was  as  active  and  intelligent  as  women  of  her 
class  in  general.  This  observation  led  to  a train  of  re- 
flections which  terminated  in  Dr.  Gall  separating, 
artificially,  the  two  laminse  of  the  convolutions  of  the 
brain. 

His  plan  is  to  remove  the  pia  mater  from  the  whole 
surface  of  the  brain,  and  then  to  introduce  the  fingers 
through  the  inferior  part  of  the  brain  into  the  inferior 
process  of  the  lateral  ventricle  along  the  course  of  the 
tsenia  striata.  By  this  means  they  may  be  carried  into 
the  body  of  the  lateral  ventricle,  and  by  gently  extend- 
ing and  separating  them,  the  convolutions  are  easily 
unfolded  into  a membrane  without  destropng  their 
fibres.  During  this  operation  a slight  resistance  is  felt 
at  the  circumference  of  the  ventricles,  and  at  the  base 
of  the  convolutions,  at  the  place  where  the  diverging 
and  converging  fibres  cross  each  other.  But  the  tissue 
which  connects  them  being  lacerated,  the  remainder  of 
the  separation  is  efiected  without  much  difficulty.  All 
the  interior  of  the  cerebral  expansion,  thus  produced, 
resembles  a case  of  hydrocephalus:  the  fibrous  sti’uc- 
ture  being  unimpaired,  white,  and  smooth,  and  covered 
externally  by  the  cineritious  matter. 

The  crossing  of  the  two  orders  of  fibres  is  easily  de 


BRAIN  AND  SPINAL  MARROW. 


99 


monstrated,  but  they  cannot  be  detached  from  each 
other  without  tearing  their  texture;  this,  however, 
may  likewise  take  place  in  hydrocephalus,  by  the  slow 
and  uniform  pressure  of  the  water  continually  increas- 
ing in  the  ventricles. 

A much  easier  way  to  demonstrate  the  convolution 
as  consisting  of  two  layers,  is  to  remove  it  from  the 
rest  of  the  cerebral  mass  and  to  make  a transverse  cut 
through  it,  from  its  summit  to  its  base ; by  a gentle 
pressure  then  with  the  finger  and  thumb  from  the 
summit  to  the  base,  the  two  laminae  of  fibrous  matter 
may  be  readily  separated  from  each  other,  leaving 
their  faces,  which  were  in  contact,  smooth  and  unin- 
jured. 

Take  a section  of  the  periphery  of  the  hemisphere 
which  has  been  detached  a little  distance  from  the  cir- 
cumference of  the  ventricles,  and  consequently  nearer 
the  surface  than  the  intertexture  which  unites  the  di- 
verging and  converging  fibres.  If  the  convex  part  of 
this  be  laid  in  the  palm  of  the  hand  so  as  to  allow  the 
weight  of  the  section  to  operate  in  drawing  tlie  convo- 
lutions asunder,  a very  slight  additional  elfort  will  be  suf- 
ficient to  separate  them  and  to  show  that  their  laminae  are 
only  agglutinated  to  each  other.  While  this  process 
is  going  on,  a little  groove  or  fissure  is  seen  at  the  place 
of  separation,  as  well  as  the  perpendicular  direction  of 
the  fibres  and  of  the  blood-wessels. 


i.oo 


OF  THE  HEAD  AND  NECK. 


Let  the  sections  of  the  brain  be  hardened  for  some 
time  in  alcohol,  or  in  nitric  or  muriatic  acid  diluted 
with  alcohol,  or  be  boiled  in  oil  for  ten  or  twelve  mi- 
nutes, the  laminae  of  the  convolutions  may  then  be  sepa- 
rated without  difficulty,  (and  only  in  the  middle  line 
where  they  are  joined  together,)  by  pressing  from  their 
summit  to  their  base  with  the  finger  and  the  thumb. 
The  fibrous  expansion  will  be  demonstrated  clearly, 
but  there  will  be  no  vestige  or  appearance  of  lacerated 
fibres. 

The  following  experiment  is  thought  by  the  author 
of  this  system,  to  prove  incontestably  that  each  convo- 
lution consists  of  two  fibrous  layers,  and  that  these 
layers  do  not  grow  together,  but  are  lightly  adherent 
the  one  to  the  other.  By  blowing  with  a small  tube 
transversally  on  a convolution,  the  convolution  is 
broken  to  pieces,  and  no  distinct  result  follows ; but  by 
blowing  with  the  same  pipe  in  the  direction  in  which 
the  natural  fissure  of  the  convolution  is  supposed  to 
exist,  the  convolution  splits  from  top  to  bottom.  By 
trying  the  same  experiment  on  a convolution  somewhat 
depressed  at  its  summit,  it  opens  at  the  base  by  a sim- 
ple fissure,  and  at  the  superior  part  this  fissure  is  ex- 
tended towards  each  angle  by  being  bifurcated.  By 
injecting  water  in  the  direction  of  a fissure  through  a 
finely  pointed  syringe,  the  separation  of  the  convolu- 
tions is  made  with  still  greater  facility  than  with  air, 
so  that  the  water  passes  for  the  distance  of  an  inch  or 
more  into  the  convolution,  and  even  extends  itself  into 


BRAIN  AND  SPINAL  MARROW. 


101 


the  convolutions  communicating  with  this  one : of  which 
the  examiner  may  be  assured  by  cutting  olf  the  tops  of 
such  convolutions.  This  last  experiment  will  succeed 
by  injecting  the  water  in  a transverse  direction  upon  a 
convolution ; so  soon  as  the  water  has  washed  away  the 
lamina  first  opposed  to  it  and  gets  to  the  middle,  it 
extends  itself  laterally  in  the  direction  of  the  fissure 
of  the  convolution.* 

Under  the  conclusiveness  of  such  demonstrations  the 
authoi’S  of  the  system  very  justly  complain,  that  in- 
stead of  considering  the  convolutions  both  of  the  Cere- 
brum and  Cerebellum  as  consisting  of  two  laminae  of 
fibrous- matter  placed  one  against  the  other  and  cover- 
ed by  cineritious  substance,  anatomists  still  continue  to 
talk  of  a substance  in  the  convolutions,  which  is  white, 
soft,  and  pulpy. 


Of  the  JVerves  of  the  Head. 

These  nerves  are  studied  in  a way  the  reverse  of  the 
old  systematic  plan.  The  most  of  them  can  be  traced 
very  satisfactorily  to  the  medulla  oblongata,  and  there- 
fore they  are  considered  from  below  upwards.  Gall 
breaks  up  the  association  forming  the  8th  pair,  and  de- 
scribes each  as  a distinct  nerve. 

* In  all  these  experiments  on  the  convolutions,  it  is  better  to 
have  the  pia  mater  removed  previously. 


102 


OF  THE  HEAD  AND  NECK. 


The  Accessory  Nerve,  forms  a natural  com- 
munication between  the  nerves  of  the  neck  and  those 
of  the  head,  for  some  of  its  branches  arise  in  the  neck 
and  others  in  the  head.  They  all  come  from  the  pos- 
terior segments  of  the  spinal  marrow  and  medulla 
oblongata;  but  their  origin  varies  in  different  in- 
dividuals, and  in  the  two  sides  of  the  same  individual, 
sometimes  beginning  at  the  fifth,  and  sometimes  at  the 
seventh  cervical  nerves.  They  arise  for  the  most  part 
by  single  threads  which  unite  successively  into  a com- 
mon chord,  but  sometimes  these  threads  are  multiplied, 
and  then  form  a single  chord,  which  joins  with  the 
main  nerve. 

This  nerve  is  spent  upon  the  Sterno-Mastoid  and 
Scapular  Muscles,  and  upon  the  Pharynx.  Hence  the 
sympathy  of  the  stomach  and  oesophagus  with  these 
muscles.  The  convulsive  motions  of  tlie  shoulders, 
oesophagus  and  pharynx,  in  hydrophobia,  and  the  stiff- 
ness of  the  shoulder  and  sterno-mastoid  muscle  in  sto- 
mach complaints. 

The  Hypoglossal  Nerve,  arises  in  part  between 
the  Corpus  Pyramidale  and  Olivare,  and  partly  below 
them.  Its  threads  issue  after  the  manner  of  the  spinal 
nerves,  separately.  These  threads  unite  and  form  thi'ee 
or  four  fasciculi,  which  join  successively  into  a common 
chord.  The  hypoglossal  nerve  is  distributed  to  the 
tongue  and  to  all  the  muscles  attached  to  the  os  hyoides 
and  to  the  salivary  glands.  It  is  connected  also  by 


BRAIN  AND  SPINAL  MARROW. 


103 


anastomosis  to  nearly  all  the  nerves  found  in  the  neck 
and  throat.  It  does  not  taste,  but  acts  in  the  motions 
of  the  tongue  performed  in  mastication,  deglutition, 
&c.  Gall  says  its  communication  with  the  cervical 
nerves,  explains  how  the  voice  is  lost  in  injuries  of  the 
cervical  medulla. 

The  Par  Vagum,  or  Nerve  of  Voice,  arises  by 
numerous  filaments  from  the  side  of  the  medulla  ob- 
longata between  the  corpus  olivare  and  restiforme, 
nearer  the  latter.  At  their  origin  these  filaments  are 
distinct,  but  they  afterwards  unite  to  form  a flattened 
cylinder,  which  passes  out  with  the  internal  Jugular 
vein.  It  is  united  with  nearly  all  the  nerves  of  the 
neck  by  anastomosis,  and  being  distributed  to  the 
larynx,  lungs  and  stomach,  it  performs  an  extremely 
interesting  part  in  the  animal  economy.  From  this  we 
understand  how  its  injuries  impair  the  voice;  how 
nausea,  cough  and  vomiting  follow  the  tickling  of  the 
pharynx ; the  connexion  between  the  speech  and  the 
voice,  &c. ; and  the  oppression  and  cough  from  sordes 
in  the  stomach. 

The  Glosso-Pharyngeal  Nerve,  composed  of 
several  filaments,  arises  from  the  medulla  oblongata  near 
the  tuber  annulare,  and  just  above  the  par  vagum.  It 
is  united  by  ramifications  in  the  neck  to  the  facial  and 
sympathetic,  and  is  spent  upon  the  constrictors  of  the 
pharynx,  and  the  muscles  of  the  tongue. 


104 


OF  THE  HEAD  AND  NECK. 


All  the  nerves  as  yet  described  correspond  veiy 
closely  with  those  of  the  spinal  marrow,  inasmuch  as 
they  arise  in  the  cineritious  substance  placed  interiorly 
in  regard  to  the  point  at  which  they  issue,  and  unite 
into  one  or  several  fasciculi.  The  nerves  that  follow 
have  the  peculiarity  of  being  successively  produced  by 
cineritious  substance,  and  of  uniting  in  the  cerebral 
mass  into  a fasciculus  which  rises  towards  its  surface, 
being  more  or  less  visible  according  to  circumstances. 

The  Motor  Externus.  The  origin  of  this  nerve 
is  better  seen  in  the  bullock  or  sheep  than  in  the  hu- 
man subject.  In  man  it  sometimes  appears  to  come 
from  the  tuber  or  medulla  oblongata,  or  from  between 
the  two,  according  to  the  breadth  of  the  tuber.  But 
arising,  in  fact,  from  the  lower  part  of  the  medulla 
oblongata,  it  ascends  the  whole  length  of  the  pyra- 
mids at  their  side  in  the  form  of  a little  fasciculus, 
and  divides  commonly  behind  the  pons  into  two  smaller 
fasciculi  which  depart  from  the  common  mass  of  the 
medulla,  one  behind  the  other.  The  pons  varolii  be- 
ing much  larger  in  man  than  in  the  animals  just  men- 
tioned, frequently  some  of  its  transverse  fibres  cover 
the  motor  externus  at  its  point  of  departure.  In  this 
case  it  appears  to  arise  from  the  pons,  and  as  its  fila- 
ments do  not  all  come  from  the  same  place,  a different 
origin  is  assigned  to  them. 


The  Facial  Nerve  is  considered  to  arise  from  the 


BRAIN  AND  SPINAL  MARROW. 


105 


place  of  union  between  the  pons,  medulla  oblong,  and 
crus  cerebelli,  but  its  origin  is  better  illustrated  in  the 
sheep  than  in  the  human  subject,  in  the  former  of 
which  it  departs  from  the  medulla  below  the  posterior 
edge  of  the  pons.  It  ascends  as  a fasciculus  in  the 
medulla  oblongata  between  the  corpus  pyramidale 
laterale  and  the  glosso-pharyngeal  nerve,  to  a trans- 
verse band  at  the  back  edge  of  the  pons  in  these  ani- 
mals. Passing  below  this  band  it  pierces  it  at  the 
internal  edge  of  the  auditory  nerve.  When  in  the 
human  subject,  there  is  an  appearance  of  this  nerve 
arising  from  the  pons,  it  is  a consequence  of  the  pons 
being  broad  enough  to  conceal  a part  of  its  origin. 

This  nerve  explains  the  motions  of  the  face  in  laugh- 
ing or  in  crying,  and  the  pains  in  the  head  and  ears 
during  the  toothach. 

The  Auditory  Nerve.  On  the  anterior  face  of 
the  fourth  ventricle,  transverse  white  medullary  strise 
exist,  supposed  to  be  the  origin  of  this  nerve.  These 
strim  vary  in  number  and  distinctness  in  different  in- 
dividuals, being  arranged  sometimes  in  rays,  occasion- 
ally as  pencils,  at  other  times  they  are  parallel.  Often 
those  of  one  side  are  higher  than  those  of  the  other; 
sometimes  they  form  little  bands  and  then  again  are 
rounded  and  projecting,  being,  in  all  cases,  separated 
from  each  other  by  a fissure  in  the  median  line.  Gall 
says  he  has  never  seen  their  decussation  from  the 
opposite  sides,  spoken  of  by  Portal.  Many  of  these 


o 


106 


OF  THE  HEAD  AND  NECK. 


medullary  strisB  go  to  the  auditory  nerve,  but  others 
go  in  part  to  the  anterior  lobules,  or  thrust  themselves 
into  the  middle  of  the  cerebellum. 

Mammiferous  animals  want  these  medullary  striae; 
one  may,  therefore,  assert  confidently,'  that  many  of 
the  filaments  of  the  auditory  nerve  arise  in  the  cineri- 
tious  substance  of  the  fourth  ventricle.  This  cineri- 
tious  substance  is  in  less  quantity  in  man,  but  forms  an 
oblong  elevation  called  Ruban  Gris  by  the  French 
anatomists;  in  the  sheep,  hog,  horse,  ox,  it  is  the 
size  of  a pea.  This  body  may  be  considered  the  gan- 
glion of  the  auditory  nerve,  and  is  placed  precisely 
where  this  nerve  winds  around  the  corpus  restiforme, 
its  size  being  always  proportionate  to  that  of  the  audi- 
tory nerve. 

In  animals,  immediately  behind  the  pons  a large 
transverse  band  is  extended  from  one  auditory  nerve 
to  the  other,  which  passes  above  all  the  other  ascending 
nervous  fasciculi  with  the  exception  of  the  pyramids. 
In  man  it  is  covered  by  the  posterior  part  of  the  pons, 
and  is  considered  by  Gall  as  a commissure  of  the 
auditory  nerves. 

The  Trigeminus,  or  5th  Pair.  Comparative  ana- 
tomy affords  the  surest  aid  in  regard  to  the  origin  of 
this  nerve,  also,  according  to  Gall.  In  fish  the 
ganglion  from  which  this  nerve  proceeds  is  insulated, 
and  its  nervous  fibres  from  tlieir  beginning  are  separa- 


BRAIN  AND  SPINAL  MARROW. 


107 


ted  from  the  common  mass.  In  mammiferoiis  animals 
a large  fasciculus  exists  at  the  exterior  edge  of  the 
under  surface  of  the  medulla  oblongata,  which  passes 
beneath  the  transverse  band  already  mentioned,  and 
projects  itself  between  it  and  the  pons.  In  the  ape 
and  in  man  this  fasciculus  is  covered  in  part  by  the 
pons,  hence  the  opinion  prevails  that  it  arises  at  the 
side  of  the  pons.  By  removing  cautiously  the  poste- 
rior part  of  the  pons  till  the  fasciculus  of  this  nerve  be 
reached,  it  will  then  be  easy  to  follow  its  entire  course 
to  the  lower  part  of  the  exterior  edge  of  the  corpus 
olivare.  In  this  manner  it  will  be  seen  very  readily, 
that  even  in  the  interior  of  the  pons  it  divides  into 
threfe  principal  fasciculi,  and  that  its  fibres  are  increased 
by  the  cineritious  substance  in  different  places.” 

The  Trochlearis,  4th  Pair,  arises  from  the  side 
of  the  valve  of  the  brain,  but  much  lower  down  than 
is  generally  supposed,  sometimes  by  one  filament, 
and  at  others  by  several.  Gall  observes,  that  at  the 
place  indicated  generally  as  its  origin,  it  only  projects 
from  the  valve,  which  is  a very  different  thing  from  its 
actual  origin. 

The  Motor  Oculi,  3rd  Pair,  issues  from  the  inter- 
nal edge  of  the  peduncles  of  the  brain  between  the  pons 
and  the  eminentise  mammillares.  Its  origin  penetrates 
to  the  third  ventricle,  but  is  separated  from  it  by  an 
interposed  stratum  of  medullary  matter.  Many  fila- 


108“ 


OF  THE  HEAD  AND  NECK. 


ments  compose  its  roots  which  are  reinforced  by  addi- 
tions from  the  cineritious  substance  called  Pons  Tarini, 
but  it  has  no  filament  from  the  eminentise  mammillares, 
as  has  been  asserted. 

The  Optic  Nerve,  in  man,  but  more  distinctly 
in  mammiferous  animals,  comes  as  a large  fasciculus  of 
fibres  from  the  nates,  winds  around  the  exterior  edge 
of  the  optic  thalamus,  where  it  is  united  to  a consider- 
able mass  of  cineritious  substance,  called  Corpus  Geni- 
culatum  Externum,  and  is  by  it  reinforced.  So  far  the 
fasciculus  is  attached  to  the  optic  thalamus,  but  after- 
wards is  only  placed  upon  the  peduncle  of  the  cerebrum 
to  which  it  adheres,  by  its  anterior  edge  being  united 
to  the  neighbouring  cerebral  fibres.  In  front  of  tliis, 
the  nerve  becomes  rounder  and  adheres  to  a firm  bed 
of  cineritious  substance,  (tuber  einereum,)  and  receives 
from  it,  particularly  above,  several  nervous  filaments 
which  unite  to  each  of  its  sides.  The  optic  nerve  is 
so  much  reinforced  by  these  filaments  that  the  increase 
of  its  bulk  is  very  perceptible,  particularly  after  its 
junction  with  its  fellow. 

In  birds  the  optic  nerve  comes  very  distinctly  from 
the  nates,  which  establishes  more  fully  that  it  must 
have  the  same  origin  in  man  and  in  the  mammalia.  In 
the  left  hemisphere  of  the  brain  of  a deranged  female, 
Dr.  Gall  found  the  thalamus  almost  destroyed  by  an 
ulcer,  the  corpus  striatum  and  the  hemisphere  much 
diminished,  but  the  optic  nerve  of  the  same  side 


BRAIN  AND  SPINAL  MARROW. 


109 


remained  entire  and  like  its  fellow.  The  nates  were 
in  a natural  state.  When,  on  the  contrary,  he  has 
found  the  optic  nerve  dwindled  away,  it  has  been  at- 
tended with  a corresponding  diminution  of  the  nates 
which  belongs  to  it.  In  the  horse,  bullock,  deer,  &c. 
the  optic  thalami  are  smaller  than  in  man,  while  the 
optic  nerves  themselves  are  larger;  no  proportion 
therefore  exists  between  them,  while  it  does  exist  as 
regards  the  nates. 

Messieurs  Gall  and  Spurzheim  believe  that  the 
optic  nerves  decussate  each  other,  and  they  quote  the 
experience  of  Dr.  Soemmering,  who  had  observed  the 
fact  in  seven  one-eyed  men;  and  in  the  horse,  the  dog, 
the  hog,  the  cat,  the  goat,  the  rat,  and  the  rabbit. 

The  Olfactory  Nerve  issues  from  the  cineritious 
substance,  in  the-  inferior  surface  of  the  hemispheres. 
Its  first  filaments  are  seen  at  the  anterior  part  of  the 
internal  convolutions  of  the  middle  lobes;  they  are  soft 
and  delicate,  and  are  surrounded  for  some  distance  by 
cineritious  substance.  These  filaments  approach  each 
other  and  form  commonly  three  principal  roots,  the 
internal  of  which  is  shorter  and  broader  than  the  two 
external.  The  most  exterior,  which  is  the  longest, 
may  be  followed  to  the  bottom  of  the  fissura  sylvii. 
These  are  the  only  nerves  of  which  there  is  any  doubt 
whether  they  take  their  origin  in  the  hemispheres  or 
not,  but  even  if  they  do,  they  are  not  continuations  of 
the  medullary  fibres  of  the  hemispheres. 


no  OF  THE  HEAD  AND  NECK. 


Section  III. 

Of  the  Eye. 

The  hairs  on  the  superior  edge  of  the  orbit  arc 
called  Supereilia,  and  on  the  edges  of  the  eyelids  the 
Cilia. 

The  Orbicularis  Palpebrarum  muscle  being  removed, 
immediately  beneath  it  are  the  two  Tarsi  Cartilages, 
which  form  the  margins  and  a considerable  part  of  the 
breadth  of  the  upper  and  of  the  lower  eyelids.  The 
upper  cartilage  is  of  a semi- oval  figure,  the  broadest 
part  being  not  quite  half  an  inch;  the  lower  cartilage  is 
of  an  uniform  breadth,  not  exceeding  in  any  part  one- 
fourth  of  an  inch.  Their  external  extremities  are 
united  with  each  other  and  kept  in  their  places  by  a 
ligamentous  expansion  connecting  them  with  the  orbi- 
tar  margin  of  the  malar  bone,  and  internally  they  are 
fixed  to  the  nasal  process  of  the  superior  maxillary 
bone  by  the  tendon  which  affords  origin  in  part  to  the 
orbicularis  palpebrarum.  The  edges  of  these  bodies 
are  slanting  so  that  a gTOOve  is  formed  posteriorly  where 
they  are  in  contact,  by  which  the  teal's  are  conducted 
to  the  inner  corner  of  the  eye.  Near  the  internal  ex- 
tremity of  each,  but  not  in  tlie  cartilage  itself,  is  to  be 
found  in  the  centre  of  a small  eminence  a foramen, 
the  Punctum  Lachrymale,  capable  of  receiving  a 


THE  EYE. 


Ill 


bristle,  and  which  being  the  orifice  of  a canal,  the 
Ductus  Lachrymalis,  conveys  the  tears  into  the  Saccu- 
lus  Lachrymalis. 

On  the  posterior  surface  of  the  tarsi  cartilages,  are 
placed  several  white  tortuous  canals  in  contact  with 
each  other,  and  having  their  extremities  on  the  edges 
of  the  eyelids;  they  are  the  glands  of  Meihomius, 
and  secrete  an  unctuous  substance.  In  the  upper  lid 
are  about  thii’ty,  and  in  the  lower  about  twenty. 

At  the  internal  junction  of  the  eyelids  is  placed  the 
Caruncula  Lachrymalis,  a small  granulated  body  infe- 
rior in  size  to  a grain  of  wheat. 

The  ball  of  the  eye  is  connected  to  the  lids  by  a de- 
licate, vascular,  and  highly  sensible  membrane,  the  Tu- 
nica Conjunctiva,  which  is  spread  over  its  anterior  third, 
not  excepting  the  cornea,  but  there  it  becomes  perfectly 
transparent.  At  the  inner  corner  of  the  eye,  the  con- 
junctiva is  thrown  into  a fold,  the  Valvula  Semilunaris, 
corresponding  with  the  membrana  nictitans  of  some 
animals. 

The  Lachrymal  Ducts  are  under  the  skin  of  the 
internal  canthus,  are  three-eighths  of  an  inch  long,  and 
terminate  by  separate  foramina  in  the  sacculus  lachry- 
nialis.  There  is  a sort  of  flap  of  tlie  internal  mem- 
brane of  the  sac  which  falls  over  these  orifices. 

The  Lachrymal  Sac  occupies  all  the  concavity 


112 


' OF  THE  HEAD  AND  NECK. 


in  the  os  unguis,  and  extends  from  a short  distance 
above  the  tendon  of  the  orbicularis  muscle  to  the  cavity 
of  the  nose,  under  the  anterior  part  of  the  inferior 
spongy  bone ; it  is  contracted  to  the  size  of  a small  crow- 
quill  at  its  nasal  orifice,  and  there  assumes  the  name  of 
Ductus  ad  Nasum.  A duplicature  of  the  membrane 
of  the  nose  resembling  a valve,  is  frequently  found  at 
this  orifice. 

The  Lachrymal  Gland  for  the  secretion  of  tears  is 
placed  in  the  superior  and  external  part  of  the  orbit, 
near  its  margin,  it  is  about  five-eighths  of  an  inch  long, 
and  half  an  inch  wide,  being  flattened  so  as  to  suit  the 
parts  with  which  it  is  in  contact.  It  is  placed  on  the  out- 
er side  of  the  tunica  conjunctiva,  and  sends  five  or  six 
small  ducts  through  it,  whose  orifices  are  in  the  tunica 
conjunctiva  of  the  upper  eyelid  near  the  external  junc- 
tion of  the  tarsi  cartilages. 

The  muscles  in  the  orbit  are  as  follow : 

1.  Levator  Palpebra:  Superioris,  arises  near 
the  superior  margin  of  the  optic  foramen,  and  is  insert- 
ed into  the  upper  margin  of  the  superior  cartilage  of 
the  eyelid.  Use,  to  di*aw  the  lid  upwards. 

2.  Levator  Oculi,  or  Rectus  Superior,  arises  from 
the  superior  margin  of  the  optic  foramen,  and  is  inserted 
into  the  upper  part  of  the  ball  of  the  eye  near  the 


THE  EYE. 


113 


cornea,  by  a flat  tendon.  It  turns  the  cornea  up- 
\vards, 

3.  Depressor  Oculi  or  Rectus  Inferior,  arises  from 
the  inferior  margin  of  the  optic  foramen,  and  is  insert- 
ed into  the  lower  part  of  the  hall  of  the  eye  near  the 
cornea.  It  draws  the  cornea  downwards. 

4.  Adductor  Oculi  or  Rectus  Internus,  arises  from 
the  internal  margin  of  the  optic  foramen,  and  is  insert- 
ed into  the  internal  part  of  the  ball  of  the  eye  near  the 
cornea.  It  draws  the  cornea  inwards. 

5.  Abductor  Oculi  or  Rectus  Externus,  arises  from 
the  external  margin  of  the  optic  foramen,  and  is  insert- 
ed into  the  external  part  of  the  ball  of  the  eye.  It  turns 
the  cornea  outwards. 

6.  Obliquus  Superior,  arises  from  the  internal 
margin  of  the  optic  foramen,  runs  along  in  contact  with 
the  orbitar  plate  of  the  os  frontis,  passes  through  the 
trochlea  near  its  internal  angular  process,  and,  being 
enclosed  in  a sheath  sent  off  from  the  trochlea,  its  round 
tendon  is  inserted  about  half-way  between  the  cornea 
and  optic  nerve  in  the  superior  and  internal  part  of  the 
eye.  It  turns  the  cornea  outwards  and  downwards. 

7.  Obliquus  Inferior,  arises  from  the  orbitar  plate 
of  the  superior  maxillary  bone  near  the  os  unguis,  and 

p 


114 


OF  THE  HEAD  AND  NECK. 


is  inserted  into  the  outer  part  of  the  eye -hall  half- 
way between  the  cornea  and  optic  nerve.  It  turns 
the  cornea  inwards  and  downwards. 

8.  Tensor  Tarsi.  At  the  internal  canthus  of  the 
orbit  is  a small  muscle  belonging  to  the  internal  commis- 
sure of  the  eye-lids  which  has  not  been  properly  ob- 
served before  and  is  omitted  in  the  descriptions  of  the 
part  given  by  the  most  eminent  writers  on  Anatomy. 
That  it  does  not  belong  to  either  of  the  above,  or  to 
the  Orbicularis  Palpebrarum,  a reference  to  very  minute 
accounts  of  them  by  the  best  authorities  will  prove. 

This  muscle  is  about  three  lines  broad  and  six  lines 
long ; it  arises  from  the  posterior  flat  surface  of  the  os 
unguis  near  its  junction  with  the  os  sethmoides,  and 
passes  forwards  and  outwards,  lying  on  the  posterior  face 
of  the  lachrymal  ducts.  As  it  approaches  the  commissure 
of  the  lids,  it  splits  into  two  parts  nearly  equal,  each  of 
which  is  appropriated  to  a duct,  and  inserted  along  its 
course  almost  to  the  punctum  lachrymale. 

To  get  a distinct  view  of  it,  the  eyelids  must  be  se- 
parated from  the  eye  and  turned  over  the  nose,  leaving 
the  tendinous  attachment  of  the  orbicularis  and  ciliaris 
muscles.  The  valvula  semilunaris  being  brought  into 
sight  by  this  process,  must  be  dissected  away,  and  also 
the  fat  and  cellular  membrane  underneatli  it.  The  mus- 
cle is  now  seen,  and  by  passing  bristles  through  the 
lachrymal  ducts  its  connexion  \\T,th  them  is  rendered  evi- 
dent, at  the  same  time  that  we  get  a good  idea  of  its  size. 


THE  EYE, 


115 


origin,  and  insertion.  While  making  this  inspection,  by 
turning  the  muscle  somewhat  aside,  we  shall  be  ren- 
dered sensible  of  another  fact  of  some  importance,  that 
the  attachment  of  the  inner  commissure  of  the  eye-lids 
to  the  internal  canthus  of  the  orbit  is  imperfectly  des- 
cribed, even  by  miatomists  of  much  minuteness  in  their 
accounts.  It  is  attributed  exclusively  to  the  tendon  of 
the  orbicularis  muscle,  so  much  so  that  in  the  opera- 
tion for  fistula  lachrymalis  we  are  strictly  enjoined  not 
to  cut  through  the  tendon,  lest  a puckering  of  the  eye- 
lids be  produced  by  their  line  of  extension  being  de- 
stroyed. The  fact,  on  the  contrary,  is,  that  a ligamentous 
matter  behind  this  tendon  passes  between  the  internal  ends 
of  the  eyelids  and  the  posterior  flat  surface  of  the  os  un- 
guis, so  that  admitting  the  tendon  of  the  orbicularis  to 
be  cut  through,  this  ligament,  assisted  by  the  little  mus- 
cle described,  would  prevent  the  dreaded  deformity. 
The  internal  extremity  of  this  posterior  ligament  is  at 
least  half  an  inch  from  the  insertion  of  the  orbicularis 
tendon  into  the  nasal  process,  and  it  brings  the  eyelids 
into  the  curve  commonly  seen  at  their  junction.  The 
lachrymal  ducts  are  involved  in  this  posterior  ligament, 
passing  along  it  into  the  sac  instead  of  going  along  the 
edges  of  the  commissure,  as  commonly  described,  just 
under  the  skin. 

The  muscle  attempted  to  be  described  must  influence 
considerably  the  position  of  the  puncta  lachrymalia  by 
drawing  them  towards  the  ball  of  the  eye  and  keeping 
them  in  close  contact  with  it;  it  is,  therefore,  a very 


116 


OF  THE  HEAD  AND  NECK* 

ejBicient  means  for  regulating  so  far  the  lachrymal  pass- 
ages and  for  securing  the  course  of  the  tears.  I am  in- 
debted to  Dr.  Physick  for  a further  suggestion  in 
regard  to  its  use,  which  appears  highly  probable. 
In  cases  of  extreme  emaciation  it  is  well  known  that  the 
adipose  matter  around  the  ball  of  the  eye  is  more  or 
less  absorbed,  causing  the  eye  to  sink  deeper  into  the 
orbit,  and  consequently  to  retire  somewhat  from  the 
lids.  The  effect  of  the  muscle  is  to  draw  the  lids  back- 
wards and  to  keep  them  applied  on  the  ball.  Again, 
in  the  elevation  of  the  upper  lid,  or  rather  the  draw- 
ing of  it  within  the  orbit  by  the  levator  palpebrse,  the 
tendency  of  the  margin  of  the  lid  is  to  leave  the  ball ; 
the  upper  part  of  the  little  muscle  ob\dates  this  ten- 
dency. As  such  appears  to  be  the  actions  of  the  part, 
I must,  therefore,  coincide  with  him  in  calling  it  Ten- 
sor Tarsi,  a name  expressive  of  its  functions. 

I am  acquainted  with  a lady  and  a gentleman  who 
possess  in  a striking  degree,  the  use  of  this  muscle,  its 
action  in  them  being  increased  much  beyond  what  is 
commonly  observed.  It  is  demostrated  by  an  ability 
to  draw  both  the  eyelids  of  one  eye  towards  the  nose, 
at  the  same  time  shortening  so  much  the  space  between 
the  puncta  lachrymalia  and  the  junction  of  the  eyelids, 
that  the  puncta  are  buried  in  the  corner  of  the  eye  and 
carried  out  of  sight. 

It  would  be  interesting  to  know  what  is  its  healthy 
influence  on  the  condition  of  the  sacculus  lachrymalis 
and  lachrymal  ducts  in  forwarding  the  tears  from  the 


THE  EYE. 


117 


eye  to  the  nose,  and  whether  we  are  right  in  attribut- 
ing this  circumstance  entirely  to  the  capillary  attrac- 
tion of  the  pi^cta  and  to  the  pressure  of  the  orbicu- 
laris muscle.* 

It  is  somewhat  surprising  that  the  idea  of  an  appara- 
tus, more  perfect  than  what  is  commonly  described  for 
regulating  the  position  of  the  puncta  lachrymalia,  had 
not  occurred  before,  and  that  anatomists  in  the  dissec- 
tion of  the  part  had  not  observed  it.  The  latter,  I 
think,  has  arisen  from  the  manner  in  which  the  dissec- 
tion for  the  muscles  of  the  eyelids  is  generally  perform- 
ed; removing  the  skin  and  exposing  the  orbicularis 
and  ciliaris  muscles,  we  think  the  dissection  completely 
made,  whereas  this  highly  interesting  part  of  the  struc- 
ture is  unattended  to.  Also  in  working  for  the  lachry- 
mal ducts  and  sac  this  muscle  is  indiscriminately  cut 
away  with  the  orbicularis. 

The  puncta  lachrymalia  have  a power  noticed  by 
Richter,  of  projecting  themselves  beyond  the  plane  of 
the  eyelid  in  which  they  lie,  and  have  an  equally  obvi- 
ous power  of  retracting  themselves  so  as  to  do  away  all 
appearance  of  prominence.!  I do  not  understand  the 
cause  of  the  first  motion,  but  the  second  depends  upon 
the  muscle  just  described. 

The  Ball  of  the  Eye  is  composed  of  several  coats  and 
humours.  As  the  human  subject  can  seldom  be  obtain- 

* Chapman’s  Journal  for  1824. 

tMy  attention  was  first  called  to  it  by  Dr.  Harlan. 


118 


OF  THE  HEAD  AND  NECK. 


ed  sujSiciently  fresh  for  a proper  display  of  the  struc- 
ture,  it  is  recommended  to  use  the  eyes  of  sheep,  bul- 
locks, or  pigs,  which  can  be  got  at  any  ^e.  The  eye 
is  to  be  removed  from  the  orbit  and  cll^ired  of  its  fat, 
and  muscles.  Anatomists  have  devised  various  means 
for  fixing  it  for  dissection,  and  any  of  them  will  answer 
sufficiently  well ; for  my  own  part  I have  never  found 
any  thing  necessary  besides  a common  saucer,  and  water 
enough  in  it  to  float  the  organ ; the  specific  gravity  of 
this  fluid  approaches  so  nearly  to  that  of  the  eye,  that 
it  affords  a very  good  support  to  its  delicate  membranes, 
and  sufficient  stability  for  most  purposes  of  examina- 
tion. 

The  Tunica  Sclerotica,  the  first  coat  of  the  eye,  is  to 
be  examined  by  opening  the  ball  very  freely  and  turning 
out  all  of  its  contents.  We  shall  then  see  that  it  has 
considerable  thickness,  being  of  a compact  fibrous  tex- 
ture, possessed  of  little  elasticity,  and  therefore  well  cal- 
culated for  giving  support  to  the  interior  structure.  It 
is  white  and  tendinous  like  the  dura  mater,  and  has  few 
vessels  or  nerves.  It  is  connected  behind  to  the  optic 
nerve,  where  it  is  perforated  by  several  small  holes  for 
the  passage  of  the  nerve,  and  before  to  the  Cornea. 

The  Cornea  is  a pei’fectly  transparent  membrane, 
consisting  of  many  laminae  united  by  a delicate  cellular 
substance.  It  is  much  more  convex  than  the  sclerotica, 
and  is  united  to  it  by  a broad  sloping  edge,  where  the 


THE  EYE. 


119 


two  membranes  adhere  very  firmly  to  each  other,  by  the 
sclerotica  overlapping  the  cornea.  They  may  be  sepa- 
rated by  putrefaction.  The  cornea  in  a healthy  state  has 
no  red  blood  circulating  through  it.  It  is  covered ; be- 
fore by  the  tunica  conjunctiva,  which  there  becomes  as- 
similated in  its  sensible  properties  to  it ; and  behind  by 
the  capsule  of  the  aqueous  humour. 

An  eye  being  floated  in  the  manner  just  mentioned, 
a puncture  is  to  be  made  with  a lancet  or  sharp-point- 
ed scalpel,  through  the  sclerotica  about  half  way  from 
its  centre ; and  the  blunted  blade  of  a pair  of  scissors 
being  introduced  through  the  opening,  a circular  cut 
should  be  made  all  around,  taking  great  care  not  to  in- 
jure the  coat  below.  By  making  radiated  sections  to 
the  optic  nerve  from  this  circular  one,  we  shall  be  able 
to  peel  off,  with  but  little  difficulty,  all  the  posterior 
part  of  the  sclerotica,  observing  however,  to  leave  the 
optic  nerve.  What  remains  of  the  anterior  part  of  the 
sclerotica  may  be  easily  drawn  away  along  with  the 
cornea.  This  stage  of  the  dissection  gives  a good  view 
of  the  Tunica  Choroides  ; of  a white  circle  called 
the  Ciliary  Ligament  seeming  to  terminate  it  before, 
and  of  the  Iris  placed  upon  the  fore  part  of  the  eye, 
an  opening  in  the  middle  of  which  affords  a glimpse  of 
the  internal  structure. 

The  Tunica  Choroides  lines  all  the  interior  of  the 
sclerotica  and  is  a much  thinner  and  more  delicate  mem 


120 


OF  THE  HEAD  AND  NECK. 


brane  than  it;  it  appears  blacky  and  is  covered  on  the 
outside  with  a flocculent  cellular  substance  connecting 
it  with  the  sclerotica.  Its  black  colour  depends  upon  a 
large  quantity  of  colouring  matter  deposited  principally 
on  its  inner  surface,  and  called  Pigmentum  Nigrum. 
The  tunica  choroides  abounds  with  blood-vessels,  which 
make  it  look  perfectly  red  in  living  animals  devoid  of 
the  black  pigment.  It  has  a singular  arrangement  of 
veins  which  can  be  made  distinct  only  by  injection. 
They  are  called  Vasa-Vorticosa.  It  is  well  furnished 
with  nerves,  which  appear  like  flattened  pieces  of  white 
thread  lying  on  its  outside.  If  the  Iris  be  torn  away, 
the  anterior  edge  of  the  membrane  is  seen  terminating 
in  a fringe  called  Corpus  Ciliare,  and  this  fringe,  if 
closely  observed,  will  be  seen  to  consist  of  a great  num- 
ber of  short  and  distinct  processes,  covered  with  pig- 
mentum nigrum. 

The  Iris  is  a membrane  placed  across  the  eye  just 
behind  the  cornea;  it  is  highly  vascular,  but  ha%-ing  a 
large  quantity  of  pigmentum  nigrum  on  its  posterior 
surface,  the  vessels  are  not  evident  in  a Imng  state.  Its 
anterior  surface  determines  the  colour  of  the  eye.  In 
its  centre  is  a round  hole  called  the  Pupil,  for  admit- 
ting light,  which  is  increased  or  diminished  by  the  ac- 
tion of  circular  and  radiated  fibres  composing  the  body 
of  the  membrane.  In  the  foetus  the  pupil  is  closed 
by  the  Membrana  Pupillaris  till  the  seventh  month. 


THE  EYE. 


121 


The  Ciliary  Ligament  is  a circle  of  whitish  sub- 
stance, consisting  of  shortfibres,  which  are  placed  around 
the  anterior  part  of  the  eye,  and  serve  to  connect 
strongly  the  Iris  with  the  Tunica  Choroides ; and  these 
again  with  the  anterior  edge  of  the  Sclerotica  and  the 
margin  of  the  cornea.  In  it  is  a canal  called  the 
Aqueduct  of  Fontana. 

Having  finished  the  examination  of  these  parts; 
with  two  pair  of  fine  forceps  strip  olf  the  whole  of  the 
Tunica  Choroides.  This  is  one  of  the  nicest  manipula- 
tions in  the  whole  dissection,  and  must  therefore  be 
done  with  great  care.  If  it  be  well  executed,  the  most 
delicate  membrane  in  the  human  frame,  will  be  found 
lining  the  choroid  coat;  it  was  lately  discovered  in  Dub- 
lin, by  Mr.  Jacobs,  and  may  be  satisfactorily  demon- 
strated, by  commencing  at  the  optic  nerve  with  the  ex- 
tremity of  a knife-handle,  and  turning  the  membrane 
down,  by  scraping  towards  the  anterior  part  of  the  eye. 
It  extends  from  the  optic  nerve  to  the  anterior  edge  of 
the  Retina. 

Beneath  the  Tunica  Jacobi,  is  placed  the  Retina,  a 
delicate,  transparent,  and  pulpy  membrane,  extending 
from  the  optic  nerve  distinctly  to  the  commencement  of 
the  Ciliary  Striae  of  the  Choroid  Coat;  and  some  anato- 
mists maintain  that  it  goes  on  as  far  as  the  circumference 
of  the  Crystalline  Humour,  which  is  by  no  means  so  ob- 
vious. The  optic  nerve,  after  penetrating  the  cribri- 

Q 


122 


OF  THE  HEAD  AND  NECK. 


form  part  of  the  Tunica  Sclerotica,  forms  a bulb  on  its  in- 
side; from  this  bulb  the  membrane  called  Retina,  is  ex- 
panded over  the  interior  surface  of  the  eye.  The  Retina 
consists  of  two  layers ; the  internal  is  a very  delicate 
and  a vascular  net- work,  consisting  of  fine  meshes ; the 
external  is  the  proper  nervous  matter,  having  a con- 
sistence not  much  stronger  than  common  mucus.  In 
the  centre  of  the  optic  nerve  is  seen  the  artery  which 
supplies  the  Retina,  called  the  Arteria  Centralis ; the 
branches  of  veins  correspond  with  the  arterial  ramifica- 
tions, and  it  is  the  former  which  we  commonly  see  dis- 
tended with  blood  in  our  dissections.  In  the  centre  of 
the  Retina  is  the  foramen  of  Soemmering,  surrounded 
by  a yellow  spot,  and  having  a fold  connecting  it  to  the 
bulb  of  the  optic  nerve.  Impressions  made  on  the 
Retina  are  supposed,  generally,  to  be  the  cause  of 
vision,  and  of  the  contractions  and  dilatations  of  the 
pupil.  Dr.  Physick  believes,  in  regard  to  the  latter, 
that  the  Iris  is  immediately  stimulated  by  the  light,  as 
he  has  seen  cases  where  the  motions  of  it  were  activ^e, 
and  well  marked  in  paralysis  of  the  Retina. 

The  Humours  of  the  Eye  are  three,  the  Vitreous, 
Crystalline,  and  Aqueous.  They  are  all  perfectly 
transparent,  but  differ  much  in  their  consistence  and 
structure. 

The  Vitreous  occupies  nearly  all  the  eye  posterior  to 
the  Iris;  it  is  like  melted  glass,  from  whence  its  name. 
When  minutely  examined,  it  is  found  to  consist  of  a 
fluid  like  water  contained  in  a very  delicate  membrane 


THE  EYE. 


123 


or  capsule,  which  is  cellular;  the  peculiar  consistence  of 
it  is  therefore  derived  from  the  latter.  This  capsule, 
called  Tunica  Hyaloidea,  is  fixed  at  the  bottom  of  the 
eye  by  a branch  of  the  central  artery  of  the  Retina, 
and  before,  by  a close  adhesion  to  the  Ciliary  Body. 
The  Retina  lies  loose  upon  it. 

The  Crystalline  Humour  is  fixed  on  the  anterior  part 
of  the  Vitreous  just  behind  the  pupil.  It  is  a double 
convex  lens,  about  three  and  a half  or  four  lines  in  di- 
ameter, the  posterior  convexity  of  which  is  mbch  the 
greatest.  Its  consistence  is  that  of  half  dissolved  glue, 
but  it  becomes  more  solid  towards  the  centre.  By  put- 
ting it  in  boiling  water  for  half  an  hour,  it  becomes 
hard  and  opake,  and  one  is  enabled  to  unravel  its 
structure.  It  consists  entirely  of  concentric  lamellse, 
■which,  with  a needle,  may  be  separated  into  very  fine 
fibres.  It  is  enclosed  in  a capsule  of  the  same  shape, 
and  between  it  and  the  capsule  is  found  a small  quantity 
of  transparent  fluid  called  Liquor  Morgagni.  Anato- 
mists do  not  agree  in  regard  to  the  origin  of  the  cap- 
sule, some  thinking  that  it  is  entirely  derived  from  the 
tunica  hyaloidea,  others  that  it  is  totally  distinct  from 
it.  The  Professor  of  Anatomy  in  this  University,  is 
decidedly  in  favour  of  the  first  opinion ; and  common  in- 
spection on  the  sheep’s  eye  favours  it;  the  tunica  hy- 
aloidea there  approaches  the  circumference  of  the  lens, 
and  then  splits  into  two  laminae,  one  going  before  and 
the  other  behind  it.  But  if  this  be  really  the  case, 


124 


OF  THE  HEAD  AND  NECK. 


the  stnicture  of  the  tunica  hyaloidea  is  unquestionably 
much  altered,  especially  in  front,  as  the  capsule  there 
is  possessed  of  more  thickness,  is  elastic,  and  cuts  very 
much  like  the  thin  shavings  of  a finger  nail,  which  in- 
duce me  to  believe  in  the  separate  existence  of  the 
capsule.  In  the  tunica  hyaloidea  surrounding  the  cir- 
cumference of  the  capsule  of  the  lens,  is  placed  the 
Canal  of  Petit,  which,  when  inflated  or  injectedis  seen  to 
be  divided  in  a radiated  manner  by  a number  of  incom- 
plete partitions. 

The  Aqueous  Humour  is  placed  between  the  lens 
and  the  cornea,  and  is  nearly  as  thin  as  water.  The 
Iris  floats  in  it,  which  has  occasioned  the  division  of 
the  space  occupied  by  the  aqueous  humour  into  An- 
terior and  Posterior  Chambers  of  the  Eye ; all  the 
space  of  the  aqueous  humour  behind  the  Iris  is  called 
the  Posterior  Chamber,  and  all  the  space  before  the 
Iris  is  called  Anterior  Chamber.  Both  of  these  cham- 
bers are  said  by  M.  J.  Cloquet  to  be  lined  by  the  cap- 
sule of  the  aqueous  humour;  this  membrane,  however, 
is  not  very  evident  except  on  the  posterior  surface  of 
the  Cornea. 

The  ball  of  the  eye  and  the  muscles  surrounding  it, 
are  imbedded  in  a considerable  quantity  of  adipose 
matter,  the  profusion  of  which,  in  health,  gives  pro- 
minence to  the  organ ; and  the  absorption  of  which,  in 
disease,  produces  the  sunken  eye. 


THE  EYE. 


125 


Of  the  Vessels  and  JVerves  met  ivith  in  the  Orbit. 

To  display  these  parts,  the  roof  of  the  orbit  must 
be  entirely  removed.  The  Internal  Carotid  Artery,  as 
it  lies  near  the  anterior  clinoid  process  of  the  Sphenoid 
Bone,  detaehes  a large  branch  the  Ophthalmic ; which 
in  passing  through  the  optic  foramen  is  first  under  the 
optic  nerve,  then  gets  to  the  outside  of  it,  and  finally 
winds  over  to  the  inside  of  the  nerve.  Near  the  pos- 
terior part  of  the  eye  it  sends  off*  a branch  which  pene- 
trates to  the  centre  of  the  optic  nerve,  and  is  distri; 
buted  to  the  retina.  It  also  divides  into  several 
branehes  which  go  to  the  Laehrymal  gland; — to  the 
muscles  of  the  Eyeball; — to  the  Tunica  Choroides,  con- 
stituting the  Ciliary  Arteries; — and  finally,  branches 
which  pass  through  the  anterior  and  posterior  sethmoi- 
dal  foramina  and  through  the  superciliary  foramen.  At 
the  bottom  of  the  orbit,  and  coming  out  at  the  infra- 
orbitar  foramen  upon  the  face,  is  found  a large  branch 
of  the  Internal  Maxillary  Artery. 

The  Veins  of  the  orbit  have  very  much  the  same 
course  with  the  arteries,  some  being  connected  with  the 
facial  vein  at  the  internal  angle  of  the  eye,  and  passing 
into  the  external  jugular;  and  others,  sending  a trunk 
through  the  foramen  opticum,  which  runs  into  the 
cavernous  sinus,  and  consequently  into  the  lateral 
sinuses. 


126 


OF  THE  HEAD  AND  NECK. 


Five  trunks  of  Nerves  are  to  be  found  in  the  Orbit. 

1st.  The  Optic,  which  is  expanded  into  the  Retina. 

2d.  The  Third  Pair,  or  Motor  Oculi,  which  passing 
through  the  foramen  lacerum  superius  into  the  orbit,  di- 
vides into  two  branches.  One  goes  to  the  upper  part  of 
the  orbit,  and  is  distributed  to  the  Levator  Oculi  and  the 
Levator  PalpebrsB  Superioris ; the  other  goes  to  the 
Adductor,  the  Depressor,  and  the  Obliquus  Inferior. 
From  it  is  sent  a filament  which  runs  to  the  Lenticular 
or  Ophthalmic  ganglion;  the  latter  is  situated  on  the  out- 
side of  the  optic  nerve  near  its  entrance  into  the  orbit. 

3.  The  Trochlearis,  or  Fourth  pair  of  nerves,  is 
exclusively  appropriated  to  the  Obliquus  Superior 
muscle,  and  also  gets  into  the  orbit  through  the  su- 
perior foramen  lacerum. 

4.  The  Motor  Externus,  or  Sixth  nerve,  passes 
through  the  superior  foramen  lacerum  of  the  orbit,  and 
is  spent  on  the  Musculus  Abductor. 

5.  The  first  branch  of  the  Fifth  nerve,  or  the  Oph- 
thalmic, passing  also  through  the  foramen  lacerum, 
divides  into  the  Frontal,  Nasal,  and  Lachrymal.  The 
first  has  but  little  to  do  with  the  Orbit,  as  it  simply 
passes  along  its  superior  part  to  get  out  upon  the  fore- 
head, through  the  supra-orbitar  foramen  and  Trochlea 


THE  EAR. 


127 


of  the  os  frontis.  The  second  passes  along  the  inner 
side  of  the  orbit,  sends  a filament  to  the  Lenticular 
ganglion : another  through  the  anterior  sethmoidal  fora- 
men which  goes  ultimately  to  the  nose,  and  what  re- 
mains is  distributed  to  the  lachrymal  sac  and  the  con- 
tiguous parts.  The  third  branch  goes  to  the  Lachry- 
mal Gland,  whence  its  name. 


Section  IV. 

Of  the  Ear. 

The  organ  of  hearing  may,  for  the  purpose  of  study, 
be  divided  into  three  parts,  the  boundaries  of  which, 
even  by  nature,  are  well  defined;  to  wit,  the  External 
Ear,  the  Tympanum,  and  the  Labyrinth. 

1.  The  External  Ear  consists  of  the  structure  ex- 
terior to  the  head ; and  of  the  passage  called  Meatus 
Auditorius  Externus,  leading  to  the  interior  of  the 
petrous  portion  of  the  temporal  bone. 

The  part,  in  common  language  called  Ear,  is  priu‘ 
cipally  cartilaginous,  but  to  the  lower  edge  of  the  car- 
tilage is  appended  a softer  structure  consisting  of  de- 


128 


OF  THE  HEAD  AND  NECK. 


licate  granulated  adeps,  with  a kind  of  tendinous  cel  - 
lular membrane.  The  cartilaginous  portion  is  called 
Pinna,  the  other  Lobus-  The  pinna  presents  a very 
unequal  surface  both  on  the  outside  and  on  the  inside. 
The  former  being  the  part  employed  in  collecting  rays 
of  sound  and  converging  them  through  the  meatus  ex- 
ternus,  merits  our  principal  attention.  The  deep  con- 
cavity in  the  middle  of  it,  is  called  Concha.  In  tlie  up- 
per part  of  the  concha,  and  dividing  it  into  two  un- 
equal fossae,  we  find  a ridge  of  cartilage  commencing, 
which  is  traced  in  the  form  of  a scroll  along  the  cir- 
cumference of  the  pinna  till  it  terminates  insensibly  in 
the  posterior  part  of  the  lobus.  This  fold  is  the  Helix ; 
within  it  is  a ridge  of  cartilage  which  is  the  Antihelix, 
terminating  above  by  a bifurcation.  On  the  anterior 
part  of  the  concha,  and  overlapping  it  obliquely,  is  tlie 
cartilaginous  process  called  Tragus,  and  opposite  to  it 
at  the  lower  end  of  the  antihelix  is  the  Antitragus. 
Under  the  fold  of  the  helix  is  the  Cavitas  Innorainata, 
and  between  the  bifurcation  of  the  antihelix  is  the 
Scapha. 

The  Meatus  Auditorus  Externus  is  about  one  inch 
in  depth,  calculating  from  the  bottom  of  the  concha ; 
it  proceeds  obliquely  forwards  in  a 0001*80  correspond- 
ing to  the  situation  of  the  petrous  bone,  and  besides 
that,  has  a curve  with  the  convexity  upwards.  The 
internal  half  is  bony,  but  the  outer  half  is  composed  of 
cartilage  and  of  ligamentous  matter.  If  the  skin  be  re- 


THE  EAR. 


129 


moved  from  the  ear  it  will  be  seen  that  the  concha  is 
formed  not  entirely  by  cartilage,  but  at  the  bottom  of 
it,  and  connecting  it  and  the  commencement  of  the  helix 
with  the  tragus,  is  a ligamentous  expansion  which  con- 
tributes also  to  the  meatus  externus.  In  the  tragus  car- 
tilage, near  the  bone,  are  found  two  fissures  filled  up  with 
elastic  ligamentous  substance ; they  are  the  Incisurae. 
The  wdiole  of  this  arrangement  of  cartilaginous  and 
membranous  matter  is  highly  favourable  to  the  exercise 
of  the  sense,  as  the  former,  by  its  resistance,  is  well 
calculated  for  reverberating  sound,  and  the  latter  affords 
great  facility  of  motion  as  a kind  of  hinge  is  formed  by 
the  incisursB.  The  cartilaginous  is  joined  to  the  bony 
meatus  by  the  exterior  edge  of  the  petrous  bone  being 
rough  and  irregular  for  this  purpose;  there  are  also 
three  ligaments  one,  sent  to  a point  above  the  mastoid 
process,  one  to  the  zygomatic  process,  and  a third  to 
the  temporal  aponeurosis. 

The  External  Ear  is  covered  by  a delicate  skin  hav- 
ing a great  number  of  sebaceous  follicles  in  it ; as  the 
skin  descends  into  the  meatus  it  becomes  still  more  de- 
licate and  sensible,  is  beset  with  hairs,  and  under  it  are 
found,  in  considerable  numbers,  the  glandulse  cerumi- 
nosse  which  secrete  the  wax. 

On  the  external  ear  are  five  muscles,  w’hieh  can  sel- 
dom be  seen  distinctly  enough  to  merit  the  name.  On 
the  superior  and  anterior  part  of  the  helix  is  the  He- 
Ucis  Major;  on  its  inferior  part  is  the  Helicis  Minor; 

-R 


130 


OF  THE  HEAD  AND  NECK. 


on  the  anterior  side  of  the  tragus  is  the  Tragicus;  on 
the  anterior  part  of  the  antitragus  is  the  Antitragicus; 
and  on  the  cranial  side  of  the  ear  is  the  Transversus 
Auris. 

In  most  persons  there  are  also  three  muscles  appro- 
priated to  the  movement  of  the  external  ear,  upon  the 
head,  and  which,  though  sufficiently  well  developed,  are 
scarcely  ever  employed.  The  Attollens  Auricula?, 
which  arises  by  a broad  membrane  from  the  tendon 
of  the  occipito  frontalis  and  the  fascia  of  the  temporal 
muscle,  and  is  inserted  into  the  prominence  made  by 
the  Scapha  or  Fossa  Navicularis.  The  Anterior  Auri- 
culsB  which  arises  from  the  temporal  fascia  just  above 
the  posterior  part  of  the  zygoma,  and  is  inserted  info 
the  anterior  part  of  the  helix.  And  the  Retrahens 
Auriculae,  consisting  of  two  or  three  slips,  the  inferior 
of  which  arises  from  the  root  of  the  mastoid  process, 
and  is  inserted  into  the  prominence  made  by  the  concha 
below ; while  the  second  slip  arises  from  the  temporal 
bone  higher  up  than  the  former,  to  be  inserted  also 
into  the  back  of  the  concha  above  the  first.  The  names 
of  these  muscles  express  their  action. 

2.  The  Tympanum  is  situated  in  the  outer  part  of  the 
Petrous  Bone,  and  is  separated  from  the  Meatus  Ex- 
ternus  by  a partition  called  Membrana  Tympani.  The 
meinbrana  tympani  is  placed  very  obliquely,  just  at  the’ 
bottom  of  the  meatus,  its  upper  part  being  the  out- 
ermost. It  is  not  flat,  but  has  its  centre  drawn  inwards 


THE  EAR. 


131 


by  the  handle  of  the  malleus.  It  consists  of  four  layers, 
the  cuticle,  the  true  fkin,  the  proper  membrane,  and 
the  lining  membrane  of  the  tympanum.  When  suc- 
cessfully injected,  it  shows  a high  degree  of  vascu- 
larity. The  two  outer  layers  are  easily  separated  from 
the  others,  and  do  not  partake  much  of  their  vascula- 
rity. 

The  tympanum  contains  a great  deal  of  curious  and 
interesting  structure ; its  depth  is  about  three  lines ; its 
antero-posterior  diameter,  six  lines;  and  its  vertical 
diameter  rather  more.  On  its  superior  posterior  part 
is  an  oval  opening  communicating  with  an  extensive 
cellular  arrangement  in  the  Mastoid  Portion  of  the 
temporal  bone ; and  on  its  anterior  side  is  seen  the 
canal  of  Eustachius  going  to  the  Posterior  Nares.  In 
thd  bottom  and  central  part  of  the  tympanum,  is  a 
striking  convexity,  the  Promontory,  just  above  the 
superior  edge  of  which  is  the  Foramen  Ovale,  and  be- 
low and  somewhat  behind  it,  is  the  Foramen  Rotun- 
dum.  On  the  posterior  surface  of  the  tympanum,  in 
a line  with  the  foramen  ovale,  is  a very  small  bony  pro- 
cess, the  Pyramid,  which  is  hollow,  and  has  a hole  in 
its  apex. 

Four  small  bones  are  found  in  the  tympanum,  which 
form  a chain  between  the  membrana  tyinpani  and  the 
Labyrinth ; they  are  the  Malleus,  Incus,  Os  Orbiculare, 
and  Stapes. 


132 


OF  THE  HEAD  AND  NECK. 


The  Malleus  is  placed  before  the  others,  and  con- 
sists of  a spherical  head,  a necff  'just  below  the  head, 
uniting  it  with  a tapering  handle;  a long  and  crooked 
projection  on  the  anterior  part  of  the  neck,  called  Pro- 
cessus Gracilis,  and  a short  one  on  the  outside  below 
the  other,  called  Processus  Brevis,  which  sends  out  a 
round  ligament*  to  the  edge  of  the  tympanum. 

The  Incus  resembles  somewhat  a molar  tooth,  with 
two  fangs  widely  separated,  and  one  much  longer  than 
the  other.  The  superior  and  anterior  part  of  the'body 
of  the  bone  is  excavated  for  articulating  with  the  head 
of  the  Malleus.  From  the  lower  part  of  the  body  pro- 
ceeds the  Processus  Loagus;  and  from  the  back  part 
looking  into  the  orifice  of  the  mastoid  cells  is  the  Pro- 
cessus Brevis. 

The  Os  Obbiculare  is  a flattened  sphere  about 
the  size  of  a mustard-seed,  placed  between  the  extre- 
mity of  the  long  process  of  the  Incus  and  the  Stapes. 

The  Stapes  resembles  very  much  a stirrup-iron, 
and  is  placed  horizontally  at  right  angles  with  the  mah 
leus.  It  has  a small  head,  articulating  with  the  os  or- 
biculare,  from  which  proceed  an  anterior  and  a poste- 
rior crus.  On  the  inner  side  of  each  crus  is  a fossa  run- 

* This  ligament  is  described  by  some  as  the  Laxator  Tyin- 
pani  Minor  Muscle. 


THE  EAR. 


133 


ning  its  whole  length.  The  crura  diverging  in  their 
progress  and  gently  bent,  are  united  by  a broad  base, 
which  corresponds  in  its  dimensions  with  the  foramen 
ovale  over  which  it  is  placed. 

To  get  a good  view  of  the  malleus  and  incus,  We 
must  cut  away  the  superior  margin  of  the  tympanum, 
their  bodies  will  then  be  seen  placed  vertically  and 
in  contact,  a complete  articulation  being  formed  by 
them. 

The  cavity  of  the  tympanum  is  lined  by  a delicate 
and  vascular  membrane,  continued  through  the  Eus- 
tachian tube  from  the  pharynx,  and  into  the  Mastoid 
Cells.  The  little  bones  are  all  covered  by  a reflection 
of  the  same,  and  the  foramen  rotundum  is  closed  up 
by  it. 

There  are  three  muscles  appropriated  to  the  move- 
ment of  these  bones,  t>^m  to  the  Malleus,  and  the  other 
to  the  Stapes. 

The  Laxator  Tympani,  placed  in  the  glenoid  fis- 
sure of  the  temporal,  and  arising  from  the  spinous  pro- 
cess of  the  sphenoid  bone,  is  inserted  into  the  processus 
gracilis  of  the  Malleus.  It  draws  the  Malleus  out- 
wards, and  consequently  relaxes  the  membrane  of  ^le 
tympanum. 

The  Tensor  Tympani  arises  from  the  cartilage  of 
the  Eustachian  tube,  lies  in  its  upper  bony  part,  and  is 


134 


OF  THE  HEAD  AND  NECK. 


inserted  by  a tendon  into  the  neck  of  the  malleus;  a 
little  below  the  processus  gracilis.  It  draws  the  handle 
of  the  malleus  inwards. 

The  Stapedius  occupies  the  conical  cavity  of  the 
pyramidal  process,  and  is  inserted  by  a delicate  round 
tendon  into  the  head  of  the  Stapes.  It  draws  this  bone 
backwards. 

3.  The  Labyrikth.  To  obtain  a good  view  of 
this  structure,  a foetal  bone  must  be  procured,  as 
the  labyrinth  is  more  accessible  in  it  and  nearly  as  fully 
developed  as  in  the  adult.  The  petrous  bone  here  has 
a condensed  but  thin  structure  on  its  surface,  which 
being  removed,  brings  into  view  a soft  and  cellular  bone 
easily  managed  with  a pen-knife.  By  paring  it  away- 
we  come  in  contact  with  the  labyrinth,  which  is  readih 
recognized  by  its  hardness  and  brittleness,  and  may  be 
got  out  with  but  little  trouble.  Having  proceed- 
ed thus  far,  the  labyrinth  is  seen  to  consist  of  three 
parts;  above  and  posteriorly  are  the  Semicircular 
Canals,  in  the  centre  is  the  Vestibule,  and  below  is  the 
Cochlea.  The  whole  of  this  structure  is  hollow. 

^he  Semicircular  Canals  attached  to  the  back  and 
upper  part  of  the  vestibule,  are  so  situated  that  one 
is  Superior,  another  Posterior,  and  the  third  Exterior 
The  superior  and  posterior  are  united  togetlier  at  their 
upper  extremities,  and  therefore  have  a common  cana 


THE  EAR. 


135 


entering  iiito  the  vestibule;  their  other  extremities 
are  v\idely  divergent  from  each  other,  and  enlarged, 
each  forming  an  ampulla  before  it  enters  into  the  vesti- 
bule. The  exterior  canal  is  shorter  than  the  others, 
lies  nearly  horizontal,  and  has  its  exterior  extremity 
enlarged  also  into  an  ampulla  which  is  placed  near 
the  ampulla  of  the  superior  canal.  These  three  canals, 
from  two  of  them  uniting,  have  only  five  orifices  in  the 
vestibule. 

The  Vestibule  has  a cavity  about  the  size  of  a gTain 
of  barley,  and  is  placed  just  on  the  inner  part  of  the 
bottom  of  the  tympanum.  The  foramen  ovale  is  the 
common  orifice  between  them.  On  the  superior  and 
exterior  part  of  the  cavity  contiguous  to  the  openings 
of  the  canals  is  the  semi- elliptical  depression,  and  be- 
low this  and  somewhat  more  internally  is  the  hemi- 
spherical depression,  the  recollection  of  both  of  which 
will  be  useful  to  us  at  a subsequent  period  of  the 
description.  At  the  lower  part  of  the  vestibule  is  a 
foramen  communicating  with  the  cavity  of  the  cochlea. 

The  Cochlea,  consists  of  a conical  tube  wound  spirally 
two  and  a half  times  on  itself,  and  is  fixed  at  the 
anterior  part  of  the  vestibule.  It  has  a broad  cribri- 
form base  forming  the  bottom  of  the  meatus  auditorius 
internus,  and  an  apex  which  occasions  the  promontory 
in  the  tympanum.  Passing  from  its  base  towards  the 
apex  is  a pillar  of  bone  called  Modiolus,  on  which  the 


136 


OF  THE  HEAD  AND  NECK. 


conical  tube  is  wound.  This  pillar  tapers  almost  to  a 
point,  and  then  is  spread  out  into  a cavity  resembling 
a funnel,  from  whence  the  name  of  Infundibulum.  The 
apex  of  the  cochlea  from  its  covering  over  the  Infundi- 
bulum is  called  the  Cupola. 

When  the  conical  tube  is  cut  open  freely  a partition 
is  seen  to  divide  it  into  two  equal  portions  from  the 
base  to  the  summit.  This  partition,  called  Lamina 
Spiralis,  arises  by  two  delicate  lamellge  of  bone  with 
an  intermediate  cellular  structure  from  the  Modiolus, 
but  does  not  go  completely  across  the  canal,  for  on 
minute  examination,  the  lamina  spiralis  is  seen  to  con- 
sist besides  of  cartilage,  of  a cellular  portion  contain- 
ing a fluid,  and  of  a membrane.  These  portions  are 
called  zones,  we  therefore  have  .Zona  Ossea,  Coriacea, 
Vesicularis,  and  Membranacea.  The  lamina  spiralis 
terminates  in  the  infundibulum  by  a process  called 
Hamulus. 

The  divisions  in  the  Cochlea  thus  made  by  the 
lamina  spinalis  form  the  seal*.  The  lowest  of  these 
§calse  has  the  foramen  rotundum  looking  into  its  base, 
and  the  upper  eommunicates  by  the  foramen  at  the 
bottom  of  the  vestibule  with  the  ca\uty  of  the  vestibule. 
From  these  communications  we  have  the  names  Scala 
Tympani,  and  Scala  Vestibuli.  The  seal*  commu- 
nicate also  with  each  other  just  at  the  hamulus  in  the 
infundibulum. 

The  whole  labyrinth  is  lined  by  a highly  vascular 
membrane,  exhibited  by  our  preparations  in  tlie  uni- 


THE  EAR. 


137 


vej:‘sity,  which  seems  to  be  very  diiferent  from  common 
periosteum. 

Thus  far  the  description  has  applied  only  to  the  bony 
labyrinth,  but  by  removing  it  we  shall  find  besides  the 
vascular  membrane  just  mentioned,  the  following  parts. 
Three  Membranous  Semicircular  Canals  within  the 
bony,  conforming  to  their  figure  and  containing  a pellucid 
fluid;  these  canals  all  communicate  by  their  extremi- 
ties with  a sac  called  Alveus  Communis,  situated  in  the 
semi- elliptical  depression  of  the  vestibule. — ^Within 
the  vestibule,  and  occupying  the  hemispherical  cavity, 
another  smaller  sac  like  a bubble  filled  with  a trans- 
parent fluid;  distinctfrom  the  former,  and  called  the  sac- 
culus  Sphericus.  To  complete  this  part  of  the  descrip- 
tion of  the  labyrinth,  it  is  to  be  observed  that  between 
the  bony  and  membranous  canals,  in  the  vestibulum  on 
the  outside  of  the  sacs,  and  in  the  scalsc  of  the  cochlea, 
is  to  be  found  a transparent  fluid,  which  can  pass  from 
one  of  these  cavities  into  the  other  by  the  foramina 
already  mentioned. 

It  is  in  connexion  with  this  fluid  that  we  find  two 
supposed  aqueducts  for  its  removal,  called  after  Cotun- 
nius,  one  for  the  Vestibule,  another  for  the  Cochlea. 
The  first  arises  near  the  common  orifice  of  the  supe- 
rior and  posterior  semicircular  canals,  and  discharges 
itself  just  behind  the  meatus  auditorius  internus.  The 
other  comes  from  the  cochlea  near  the  foramen  rotun- 
dum,  and  runs  into  the  jugular  fossa  just  at  the  root  of 

s 


138 


OF  THE  HEAD  AND  NECK. 


the  spine  for  separating  the  eighth  pair  of  nervxs  from 
the  internal  jugular  vein. ^ 

The  Nerve  of  Hearing,  or  the  Portio  Mollis,  is 
distributed  throughout  the  labyrinth.  The  bottom  of 
the  meatus  internus  being  divided  into  two  unequal 
fosssB  by  a ridge ; the  uppermost  is  the  smaller  and  per- 
forated with  several  foramina,  all  of  which,  except  the 
anterior  large  one,  are  appropriated  to  the  passage  of 
the  portio  mollis  to  the  vestibule.  The  larger  fossa 
at  the  bottom  of  the  meatus  is  also  cribriform,  and  forms 
the  basis  of  the  cochlea;  through  it  pass  fibrillse  to 
the  cochlea,  vestibule,  and  semicircular  canals.  The 
portio  mollis,  descending  to  the  bottom  of  the  meatus, 
passes  in  several  divisions,  to  the  soft  structure  with 
in  the  hony  labyrinth.  One  division,  entering  the 
vestibule,  is  spent  on  the  alveus  communis  and  membra- 
nous canals;  another  division  goes  to  the  sacculus  sphe- 
ricus.  A third  division,  penetrating  from  the  base  of 
the  modiolus,  runs  through  it  and  comes  out  upon 
the  lining  membrane  of  the  cochlea,  between  the  plates 
of  the  lamina  spiralis  and  through  the  infundibulum 
and  other  parts.  The  fibrillse  of  the  portio  mollis, 
during  this  distribution,  continue  exceedingly  delicate, 
and  are  finally  found  in  a pulpy  state  resembling  the 
retina  upon  the  internal  surface  of  the  ca%ities  and  sacs 
just  mentioned. 


^M.Ribes  has  ascertained  that  they  only  conduct  blood-vessels 


THE  EAR 


139 


The  PoRTio  Dura,  though  not  concerned  in  the 
function  of  hearing,  passes  through  the  petrous  bone 
in  a curious  manner.  Entering  into  the  large  foramen 
in  the  upper  fossa  of  the  meatus  internus,  it  goes  out- 
wards almost  as  far  as  the  vidian  foramen  and  there 
makes  a very  abrupt  turn  backwards,  forming  an  acute 
angle  called  its  elbow.  It  then  runs  just  above  the 
foramen  ovale,  making  a ridge  in  the  tympanum;  con- 
tinues its  course  so  as  to  surround  the  back  part  of 
the  tympanum,  and  emerges  at  the  foramen  stylo-mas- 
toideum.  It  is  afterwards  distributed  to  the  face. 
Its  canal  in  the  bone  is  called  the  aqueduct  of  Fallo- 
pius. 

The  Chorda  Tympani,  a branch  of  the  pterygoid 
nerve,  passes  into  the  vidian  foramen  and  joins  the 
portio  dura,  running  closely  conneeted  with  it  almost 
to  the  stylo-mastoid  hole.  It  then  leaves  the  portio 
dura  at  an  acute  angle  and  enters  into  the  back  part  of 
the  tympanum,  crosses  this  cavity  completely,  by  going 
between  the  long  leg  of  the  incus  and  the  handle  of  the 
malleus.  It  gets  from  the  tympanum  through  a fora- 
men in  the  fissure  of  the  glenoid  cavity,  and  joins  ulti- 
mately the  lingual  branch  of  the  fifth  pair  of  nerves. 
It  sends  fibres  to  the  membrana  tympani  and  to  the 
muscles  of  the  malleus. 

The  labyrinth  is  principally  supplied  with  blood 
from  a branch  of  the  vertebral  artery  which  gets  to  it 
through  the  meatus  internus.  The  tympanum  and  ex- 


140 


OF  THE  HEAD  AND  NECK. 


ternal  ear  are  supplied  from  the  stylo-mastoid  and  tern 
poral  arteries. 


Section  V. 

Of  the  A^'ose, 

In  order  to  understand  this  part  of  our  structure  it 
is  necessary  to  be  well  acquainted  with  th  e bones  con- 
stituting its  cavity,  both  individually  and  collectively. 
Being  thus  prepared,  we  shall  see  that  the  nostrils 
which  are  incompletely  separated  from  each  other  in 
the  skeleton  have  a perfect  septum  in  the  recent  sub- 
ject, which  renders  them  two  distinct  cavities.  This 
is  effected  by  a cartilage  placed  at  the  anterior  parts 
of  the  vomer  and  of  the  nasal  lamella  of  the  sethmoid 
bone.  At  the  junction  of  this  cartilage  with  the  nasal 
suture  it  spreads  out  on  each  side  into  a wing,  and  is  at- 
tached to  the  lower  edge  of  the  nasal  bones,  extend- 
ing by  such  means,  the  bridge  of  the  nose. 

Proceeding  from  the  lower  edge  of  the  wing  of  this 
cartilage,  and  from  the  external  bony  margin  of  the 
anterior  naris,  is  an  elastic  ligamentous  membrane  form- 
ing the  side  of  the  nostril.  At  the  anterior  part  of 
this  membrane  is  an  oval  cartilage  which  forms  two- 


THE  NOSE. 


141 


thirds  of  a ring,  the  exterior  portion  of  it  is  the  broad- 
est ; the  internal  portion,  placed  in  contact  with  the 
corresponding  part  of  the  oval  cartilage  of  the  other 
side,  runs  backwards,  and  the  two  form  by  their  union, 
the  tip  of  the  nose  and  the  Columna  Nasi.  In  the  back 
of  the  ligamentous  membrane  there  are  several  detach- 
ed pieces  of  cartilage  which  give  firmness  to  the  struc- 
ture and  produce  the  prominence  of  the  ala  nasi.  It 
is  by  means  of  these  several  cartilages  that  the  orifice 
of  the  nostril  is  kept  open. 

The  posterior  nares,  being  separated  by  the  vomer; 
are  oval,  and  do  not  present  an  outline  differing  much 
from  that  produced  by  the  naked  bone.  At  the  poste- 
rior extremities  of  the  inferior  turbinated  bones  are  the 
orifices  of  the  Eustachian  tubes  placed  obliquely,  and 
large  enough  to  admit  the  end  of  the  little  finger.  It 
is  not  difficult  to  reach  them  with  an  instrument  gently 
curved,  introduced  through  the  inferior  meatus  of  the 
nose.  They  are  here  partly  membranous  and  partly 
cartilaginous,  running  upwards  and  outwards  to  the 
bony  canal  leading  to  the  cavity  of  the  tympanum. 

The  Schneiderian  membrane  is  spread  over  all  the 
bones  composing  the  nostril,  and  by  its  thickness  dimi- 
nishes the  foramina  leading  into  the  sinuses.  Under  the 
anterior  part  of  the  middle  spongy  bone  is  an  orifice 
which  leads  through  the  scthmoidal  cells  into  the  fron- 
tal sinus.  At  the  middle  part  of  the  middle  meatus, 
or  that  between  the  lower  and  middle  spongy  bones,  is 


142 


OF  THE  HEAD  AND  NECK. 


the  opening  into  the  Antrum  Highmorianum  capable 
of  giving  entranee  to  a common  quill.  In  the  meatUb 
formed  posteriorly  in  the  mthmoid  bone,  under  the  cor- 
net of  Morgagni,  are  the  orifices  of  the  posterior  aeth- 
inoidal  cells;  at  the  back  part  of  this  cornet,  and  a little 
above  it,  is  the  orifice  of  the  Sphenoidal  Sinus.  Imme- 
diately under  the  fore  part  of  the  inferior  spongy  bone 
is  the  orifice  of  the  Ductus  ad  Nasum.  This  membrane 
is  laid  smoothly  on  the  septum  of  the  nose. 

The  Schneiderian  or  mucous  membrane,  when  well 
injected,  shows  great  vascularity;  its  reflections  into 
the  sinuses  are  not,  however,  so  thick  or  vascular  as 
the  other  parts  of  it.  The  surface  which  looks  towards 
the  cavity  of  the  nose  is  villous  like  velvet,  and  is  stud- 
ded with  many  mucous  follicles  which  pass  obliquely 
into  it,  some  of  them  being  arranged  in  rows.  It  ad- 
heres closely  to  the  bones,  and  that  surface  in  the  close- 
ness of  its  texture  resembles  periosteum. 

Its  nerves  are  derived  from  three  sources. 

1.  The  Olfactory,  or  Nerves  of  Smelling.  They 
pass  on  each  side  of  the  crista  galli  in  two  rows  perfora- 
ting the  cribriform  plate,  and  taking  a coat  of  dura 
mater  which  renders  them  strong  and  fibrous.  One  row 
is  spread  on  the  membrane  covering  the  upper  part  of 
the  sethmoid  bone,  not  descending  below  the  inferior 
edge  of  the  middle  spongy  bone;  the  other  is  distribu- 
ted to  the  membrane  of  the  nasal  septum,  and  its  fibi*e‘^ 


THE  NOSE. 


143 


descend  somewhat  lower.  The  fibrillse  of  these  nerves 
terminate  on  the  mucous  surface  of  the  membrane. 

2.  The  Lateral  Nasal  Nerve  comes  from  the 
Spheno  Palatine  Ganglion  through  the  spheno  palatine 
hole,  and  gives  fibres  to  the  septum  and  lateral  parts 
of  the  nose.  One  of  the  former  dips  into  the  anterior 
palatine  hole,  joins  with  its  fellow  from  the  other  side, 
and  forms  a ganglion  near  the  roof  of  the  mouth. 

3.  The  Nasal  Nerve  of  the  First  Branch  of  the 
Fifth  Pair,  passing  through  the  anterior  sethmoidal 
foramen  into  the  cranium,  dips  down  at  the  side  of  the 
crista  galli  into  the  nose,  and  may  be  traced  along  the 
nasal  bone  to  the  tip  of  the  nosel 

The  nose  is  supplied  principally  with  Blood  fi’om 
the  internal  maxillary  artery  and  from  the  sethmoidal 
branches  of  the  ophthalmic.  Its  veins  accompany  the 
arteries. 


144 


OF  THE  HEAD  AND  NECK. 


Section  VI. 

Mouth. 

The  cavity  of  the  mouth  is  chiefly  formed  by  the 
palatine  processes  of  the  upper  maxillary  and  palate 
bones,  above;  by  the  tongue  and  the  muscles  connect- 
ed with  it,  below ; by  the  cheeks  laterally ; by  the  lips 
before,  and  by  tlie  soft  palate  behind. 

The  Tongue  has  its  root  at  the  os  hyoides;  it  is 
there  thin,  but  broad;  its  tip  and  sides,  owing  to  the 
lining  membrane  passing  a considerable  way  under  them 
before  it  is  reflected  to  the  organ,  are  left  free.  Four 
pairs  of  muscles  compose  its  bulk.  The  Stylo-glossus, 
which  arises  from  the  anterior  part  of  the  styloid  pro- 
cess, and  is  inserted  into  the  side  of  the  tongue  near  its 
root,  the  fibres  going  to  the  tip.  The  Hyo-glossus, 
which  arises  broad  and  thin  from  the  cornu,  appendix, 
and  body  of  the  os  hyoides,  and  forms  a considerable 
part  of  the  bulk  of  the  tongue  on  its  side.  The  Lin- 
gualis,  arising  indistinctly  from  the  root  of  the  tongue, 
on  the  inner  side  of  the  former  muscle,  and  its  fibres  are 
to  be  traced  as  far  as  the  tip.  And  lastly,  tlie  Genio- 
Hyo-glossus  muscle,  the  most  internal  of  tlie  four,  hung 
in  contact  with  its  fellow  of  the  opposite  side.  It  arises 


THE  MOUTH. 


145 


trom  the  tubercle  on  the  posterior  face  of  the  symphy- 
sis of  the  lower  jaw;  its  fibres  radiate  so  as  to  be  in- 
serted from  the  body  of  the  os  hyoides  to  the  tip  of 
the  tongue.  Besides  these  regular  and  well  defined 
rnusclesj  there  are  many  fibres  which  cross  the  or- 
gan in  various  directions  and  facilitate  much  its  mo- 
tion. 

The  superior  silrface  of  tlie  tongue  is  rough  from  the 
presence  of  a number  of  eminences  on  it,  called  Pa- 
pillae. At  the  posterior  part  are  about  nine  of  them, 
arranged  like  the  letter  V,  with  the  point  backwards, 
much  larger  than  the  others.  They  are  fixed  in  pits, 
and  surrounded  by  a fold  of  the  integuments ; from  their 
particular  form,  they  have  been  called  Papillae  Capi- 
tatae,  or  Maximae.  Distributed  over  the  tongue,  and 
scattered  at  irregular  distances  from  each  other,  are  the 
Papillae  Mediae,  more  numerous  than  the  others,  and 
smaller.  A third  class  of  them  occupies,  by  far,  the 
greater  part  of  the  surface  of  the  tongue,  and  are  call- 
ed Papillae  Villosae.  And  a fourth  set  of  them,  filling 
up  the  intervals  left  between  the  others,  and  being  the 
smallest  of  any,  are  called  Papillae  Filiformes.  It  is 
probable  that  these  papillae,  except  the  fii’st,  are  essen- 
tially connected  with  the  function  of  taste,  as  they  are 
abundantly  supplied  with  nerves  and  blood-vessels,  hav- 
ing a peculiar  arrangement. 

At  the  posterior  part  of  the  tongue  is  a fold  of  the 
membrane  covering  it,  which  rises  up  to  join  the  Epi- 
glottis cartilage;  and  within  this  duplicature  is  a liga- 

T 


146 


OF  THE  HEAD  AND  NECK. 


mentous  bridle  serving  to  keep  the  Epiglottis  cartilage 
erect ; muscular  fibres  from  the  base  of  the  tongue  form 
its  commencement.  On  each  side  of  it  is  a small  pouch 
which  occasionally  produces  some  trouble  from  articles 
of  food  lodging  in  it.  A little  anterior  to  this  fold  is  a 
small  blind  hole,  receiving  the  central  papilla  maxima 
and  into  which  some  mucous  glands  discharge  their  con- 
tents, it  is  called  the  Foramen  Caecum  of  Morgagni;, 
and  sometimes  behind  it  is  another  foramen  caecum  but 
without  a papilla.  Scattered  about  the  root  of  the 
tongue  we  find  many  mucous  glands. 

The  lining  membrane  of  the  mouth,  when  the  cuti- 
cle is  separated  from  it  by  maceration,  exhibits  a sur- 
face covered  with  fine  vilii.  On  the  lips  and  cheeks, 
under  it,  are  situated  many  small  glandular  bodies,  call- 
ed Glandulae  Labiales,  and  Buccales.  It  forms  a frac- 
num  where  it  is  reflected  from  the  upper  and  lower 
lips  to  the  centre  of  the  Jaw  Bones.  On  the  alveolar 
processes,  its  texture  is  more  dense,  constituting  the 
gums,  which  closely  surround  the  necks  of  the  teeth. 
This  membrane  is  also  united  to  the  lower  side  of  the 
tongue  by  a fi’senum,  on  each  side  of  which  we  see  the 
orifices  of  the  ducts  of  the  sub-maxillary  glands.  Under 
the  tongue,  at  its  side,  and  projecting  into  the  cavitv" 
of  the  mouth,  but  covered  by  the  lining  membrane,  is 
the  Sublingual  Gland,  opening  by  fifteen  or  twenty  dis- 
tinct orifices.  On  the  cheeks,  opposite  the  intei-stice 
t»f  the  second  and  third  molar  tooth  of  the  upper  jav  • 
is  found  the  orifice  of  the  duct  of  the  Parotid  Gland. 


thet  mouth. 


147 


The  lining  membrane  of  the  roof  of  the  mouth,  is 
of  a dense  structure,  having  a ridge  in  it  just  under  the 
middle  palate  suture,  and  on  each  side  of  that  transverse 
ridges,  extending  towards  the  alveolar  processes.  It 
adheres  very  closely  to  the  bone,  and  beneath  are  to  be 
found  many  mucous  glands  of  various  sizes,  having 
their'  excretory  ducts  terminating  on  the  surface  of  the 
palate. 

Of  the  Fauces. 

At  the  posterior  part  of  the  mouth  may  be  seen,  very 
distinctly,  by  depressing  the  lower  jaw,  an  incomplete 
partition  which  divides  it  from  the  pharynx.  It  is  the 
Velum  Pendulum  Palati,  formed  by  the  lining  mem- 
brane of  the  mouth  reflected  over  several  muscles.  In 
the  centre  is  a projection  termed  Uvula.  On  each  side 
of  the  uvula  the  soft  palate  has  its  inferior  margin  ter- 
minating in  two  crescentic  edges  called  its  lateral  half 
arches.  The  anterior  half  arch  is  rather  more  distinct 
than  the  posterior,  and  arising  from  the  side  of  the  uvula, 
runs  around  to  be  inserted  into  the  side  of  the  basis  of 
the  tongue.  The  posterior  half  arch,  arising  from  the 
side  of  the  uvula  near  the  anterior,  runs  backwards  and 
outwards,  and  is  lost  insensibly  about  the  middle  of  the 
pharynx.  Between  the  half  arches,  on  each  side,  is 
placed  the  Tonsil  Gland,  the  surface  of  which  is  com- 
monly so  reticulated,  that  it  might  readily  be  mistaken 
for  ulceration.  The  space  between  the  lateral  half 


148 


OF  THE  HEAD  ATsD  NECK. 


arches  is  the  Fauces,  and  the  anterior  opening  into  it, 
is  the  Isthmus  of  the  Fauces. 

By  dissecting  off  the  membrane  of  the  soft  palatc- 
which  is  continued  from  the  mouth,  several  mucous 
glands  are  brought  into  view  lying  immediately  under 
it,  and  also  the  muscular  structure,  which  is  as  fol- 
lows. 

1.  In  the  anterior  half  arch  is  the  Constrictor 
IsTHMi  Faucium,  which  arises  from  the  side  of  the 
tongue  near  its  root,  and  is  inserted  into  the  middle  of 
the  velum  near  the  root  of  the  uvula.  It  tends  to  close 
the  opening  from  the  mouth  into  the  pharynx. 

2.  In  the  posterior  half  arch  is  the  Palato  Pha- 
RYNGEUS.  It  arises  from  the  middle  of  the  soft  palate 
behind,  near  the  root  of  the  uvula,  and  is  inserted  in 
the  pharynx  between  the  middle  and  lower  constric- 
tors and  into  the  superior  posterior  margin  of  the 
Thyroid  Cartilage.  It  di-aws  the  velum  palati  down- 
wards. 

3.  CiRCUMFLEXUS  or  Tensor  Palati;  arises  from 
the  spinous  process  of  the  sphenoid  bone  behind  the 
foramen  ovale,  and  from  the  contiguous  part  of  the  Eus- 
tachian tube,  it  passes  in  contact  with  the  pterygoideus 
internus  muscle,  and  terminates  in  a broad  tendon  be- 
low, which  winds  around  the  hook  of  the  internal  ptery- 
goid process,  and  is  inserted  into  the  soft  palate  near 


PHARYNX  AND  CESOPHAGlJS. 


149 


Its  middle,  and  into  the  posterior  lunated  edge  of  the 
palate  bone.  It  spreads  the  palate. 

4.  Levator  Palati,  arises  from  the  point  of  the 
petrous  bone  and  contiguous  part  of  the  Eustachian 
tube ; it  is  on  the  inner  side  of  the  former  muscle,  and 
passes  downwards  to  be  inserted  into  the  soft  palate.  It 
draws  the  soft  palate  upwards. 

5.  The  Azygos  UvuLiE  arises  from  the  posterior  ter- 
mination of  the  palate  suture,  runs  through  the  centre 
of  the  soft  palate,  and  ends  in  the  point  of  the  uvula. 
It  draws  the  uvula  upwards  and  diminishes  the  verti- 
cal breadth  of  the  soft  palate. 


Section  VII. 

Of  the  Pharynx  and  CEsophagus. 

The  Pharynx  is  a large  membranous  cavity  placed 
at  the  posterior  part  of  the  nose  and  of  the  mouth  for 
opening  an  external  communication  with  the  cavities  of 
the  thorax  and  abdomen.  It  lies  before  the  cervical 
vertebrae,  being  connected  to  them  by  cellular  mem- 
brane, is  closely  attached  to  the  basis  of  the  skull  be- 


150 


OF  THE  HEAD  AND  NECK. 


fore  the  foramen  magnum,  to  the  posterior  mai*gin  of 
the  upper  and  under  jaws,  to  the  hack  parts  of  the  oe 
hyoides  and  of  the  thyroid  cartilage,  and  below  it  con- 
tracts so  as  to  be  continuous  with  the  oesophagus.  In 
consequence  of  these  several  attachments  it  constantly 
remains  a patulous  unoccupied  cavity,  having  a free 
communication  with  the  nostrils  and  Eustachian  tubes 
above,  with  the  mouth  just  below  them,  with  the 
larynx  still  lower  down,  and  with  the  oesophagus  at  its 
bottom.  The  lining  membrane  which  is  expanded 
over  it,  is  continuous  with  tlie  lining  membranes  of 
these  several  cavities. 

To  get  a good  view  of  the  pharynx,  the  head 
ought  to  be  cut  off  at  the  root  of  the  neck  and  all  the 
cervical  vertebrae  be  removed ; the  cavity  being  then 
stuffed  with  baked  hair,  we  proceed  to  the  dissection 
of  the  muscles  which  form  it,  of  which  there  are  three 
pairs, 

1.  Constrictor  Pharyngis  Inferior,  arises  from 
the  side  of  the  cricoid  and  of  the  thyroid  cartilage  ; it 
unites  with  its  fellow  in  a white  line  in  the  centre  of  the 
posterior  part  of  the  pharynx.  Its  superior  fibres  are 
very  oblique,  covering  the  lower  edge  of  the  next  mus- 
cle, and  its  inferior  fibres  are  more  transverse,  being 
connected  with  the  oesophagus. 

2.  Constrictor  Pharyngis  Medius,  arises  from 
the  appendix  and  cornu  of  the  os  hyoides,  and  from 


PHARYNX  AND  (ESOPHAGUS.  151 


the  round  ligament,  connecting  the  latter  with  the  cornu 
of  the  thyroid  cartilage.  It  is  inserted,  in  the  same 
Way  as  the  foregoing,  into  its  fellow  and  into  the  cunei- 
form process  of  the  os  occipitis  just  before  the  foramen 
magnum. 

3.  Constrictor  Pharyngis  Superior,  arises  from 
the  cuneiform  process  of  the  os  occipitis,  from  the 
pterygoid  process  of  the  sphenoid  bone,  and  from  the 
upper  and  under  jaw  bones  behind  the  last  molar  teeth 
being  connected  with  the  buccinator  muscle.  Inserted 
into  its  fellow  by  a white  line  in  the  middle,  and  hav- 
ing its  lower  edge  concealed  by  the  preceding. 

These  muscles  all'  assist  in  conveying  the  food  from 
the  mouth  into  the  oesophagus. 

The  pharynx,  after  the  dissection  of  these  muscles, 
may  be  cut  open  vertically  at  its  back  part,  when  a 
very  satisfactory  view  of  all  the  cavities  connected 
with  it  will  be  obtained.  ; 

The  (Esophagus. 

This  is  a tube  leading  from  the  pharynx  to  the  sto- 
mach, it  is  placed  between  the  trachea  and  cervical 
vertebrsB  above,  passes  into  the  thorax  between  the 
laminae  of  the  mediastinum  and  in  contact  with  the 
dorsal  vertebrae.,  penetrates  through  the  left  foramen  of 


152 


OF  THE  HEAD  AND  NECK. 


the  diaphragm  and  terminates  in  the  cardiac  orifice  of 
the  stomach.  (See  posterior  mediastinum). 

The  CEsophagus  is  formed  of-three  coats,  the  muscu- 
lar, the  nervous  and  the  mucous.  When  distended  it 
is  cylindrical,  but  larger  below  than  above.  The 
muscular  coat  is  very  strong,  consisting  of  two  planes 
of  fibres,  the  external  being  longitudinal  and  the  in- 
ternal circular.  The  nervous  coat  connects  together 
the  other  two;  it  is  formed  of  loose  cellular  membrane 
which  allows  them  to  move  very  freely  upon  each 
other,  and  conducts  the  blood-vessels  through  their 
structure.  The  mucous  coat  is  a continuation  of  that 
of  the  pharynx,  it  is  covered  by  a very  delicate  cuti- 
cle, which  is  continued  into  the  stomach,  and  forms  in 
some  animals  an  abrupt  and  well  marked  termination 
just  at  the  cardiac  orifice.  The  internal  coat  of  the 
oesophagus  is  most  frequently  found  in  longitudinal  folds, 
which  are  removed  by  its  distention ; it  abounds  with 
mucous  follicles,  and  is  well  furnished  with  blood- 
vessels. 


THE  LARYNX, 


153 


Section  VIII. 

Of  the  Larynx. 

By  the  term  Larynx  is  understood  the  irregular 
cartilaginous  tube  which  forms  the  upper  termination  of 
the  windpipe.  The  basis  of  the  structure  is  five  dis- 
tinct cartilages;  and  a crooked  bone  the  os  hyoides, 
which  is  intermediate  to  the  larynx  and  the  tongue,  ser- 
ving the  purposes  of  both. 

The  Os  Hyoides  resembles  much  the  letter  U,  di- 
visible into  its  basis  or  curved  part  and  its  cornua,  or 
lateral  projections.  It  is  parallel  with  the  lower  jaw 
and  about  half  an  inch  below  it.  It  acts  as  a root  to 
the  tongue;  as  two  arms  in  holding  out  the  bag-like 
orifice  of  the  Pharynx;  and  from  it,  is  suspended  the 
Larynx.  The  base  of  the  os  hyoides  is  broad  and 
convex  anteriorly,  above  it  is  flattened  on  each  side  by 
the  insertion  of  muscles  from  the  lower  jaw,  and  at  its 
posterior  part  it  is  excavated  sujBiciently  to  receive  the 
tip  of  the  little  finger.  At  the  ends  of  the  base  the 
two  cornua  arise,  separated  from  it  by  cartilage  and 
therefore  moveable;  they  are  about  an  inch  long,  are 
somewhat  flattened,  and  have  a tuberculated  termina- 
tion behind.  On  the  cartilaginous  interval  of  each 
side,  is  placed  a bony  body  about  the  size  of  a grain  of 

u 


154 


OF  THE  HEAD  AND  NECK. 


wheat,  the  Appendicula,  which  stands  up  obliquely 
towards  the  styloid  process  and  is  connected  to  its  tip 
by  a round  ligament  resembling  a nerve;  this  ligament 
in  some  cases  has  been  found  ossified  in  the  greater 
part  of  its  length.  The  five  cartilages  of  the  Larynx 
are  the  Thyroid,'  Cricoid,  two  Arytenoid,  and  the 
Epiglottis. 

The  Thyroid  Cartilage,  (Cartilage  Thyroidea,)  is 
about  an  inch  below  the  os  hyoides,  and  forms  a very 
striking  prominence  in  the  male  neck.  It  consists  of  two 
flat  sides  w^hich  are  symmetrical,  and  united  to  each  other 
by  an  angle  slightly  acute  at  its  anterior  part;  the  upper 
place  of  union  forms  the  projection,  called  Pomum 
Adami.  The  sides  of  this  body  lean  over  somewhat, 
by  which  its  transverse  diameter  above  is  somewhat 
larger  than  that  below.  The  upper  edge  .is  notched 
in  front,  and  terminates  behind  by  a long  process  on 
each  side;  the  Cornua  Majora,  which  look  towards 
the  ends  of  the  cornua  of  the  os  hyoides  and  are  con- 
nected to  them  by  round  ligaments.  The  inferior  edge 
is  somewiiat  incurvated,  and  terminates  behind  by 
a short  process  on  both  sides,  the  inferior  cornua,  or 
Cornua  Minora,  by  which  it  is  fastened  to  the  sides  of 
the  cricoid  cartilage  and  establishes  a centre  of  motion 
betw'een  the  two. 

The  Cricoid  Cartilage,  (Cart.  Cricoidcs,)  is  an 
oval  ring  of  unequal  breadth  and  thickness  placed  im 


THE  LARYNX. 


155 


mediately  below  the  thyroid  cartilage.  Its  lower  mar- 
gin is  horizontal  and  ajfixed  to  the  first  ring  of  the 
trachea;  the  upper  margin  is  very  oblique,  rising  from 
before  backwards,  till  the  breadth  behind  is  three 
times  as  great  as  that  before.  In  front  the  ci’icoid 
cartilage  is  thin,  behind  it  is  thick.  On  the  upper  edge 
behind,  on  each  side,  a little  head  or  convexity  is 
formed  for  establishing  a sort  of  ball  and  socket  joint 
with  the  arytenoid  cartilages.  The  interior  surface  is 
flat,  the  exterior  is  marked  by  the  muscles  which  lie 
on  it. 

The  Arytenoid  Cartilages,  (Cart.  Arytsenoi- 
deae,  Triquetrae.)  two  in  number,  one  on  each  side  of 
the  upper  back  part  of  the  cricoid,  resemble  each  a 
triangular  pyramid  curved  backwards  and  having  an 
excavated  base.  The  internal  sides  of  the  two,  face 
each  other,  and  by  the  action  of  their  muscles  may  be 
brought  together ; when  thus  joined  they  resemble  the 
spout  of  a pitcher.  On  the  top  of  each  is  a little  car- 
tilaginous tubercle  about  the  size  of  a grain  of  wheat, 
( Comic ulum  Laryngis,)  which  is  included  in  the  soft 
parts  and  is  extremely  moveable.  There  is  a regular 
articular  cavity  between  the  cricoid  and  arytenoid  car- 
tilages. 

The  Epiglottis  Cartilage,  (Epiglottis,)  is  an 
oval  disk'  with  an  elongated  pedicle  below,  its  up- 
per edge  being  thin  and  rounded.  It  is  fixed  behind 


156 


OF  THE  HEAD  AND  NECK. 


the  base  of  the  os  hyoides  and  has  its  pedicle  connected 
to  the  entering  angle  on  the  posterior  face  of  the 
^ thyroid  cartilage.  The  flat  surfaces  of  this  cartilage 
present  forwards  and  backwards,  and  are  above  the 
level  of  the  arytenoids;  from  this  position  of  the  epi- 
glottis it  is  said  to  be  placed  as  a valve  over  the  open- 
ing of  the  larynx ; its  valvular  office,  however,  I have 
great  cause  to  disbelieve,  for  subsequent  reasons.  It  is 
very  elastic,  having  a fibro-cartilaginous  structure,  and 
is  perforated  with  many  foramina  giving  it  a cribri- 
form appearance. 

The  upper  edge  of  the  Thyroid  Cartilage  is  connect- 
ed to  the  internal  edge  of  the  Os  Hyoides,  by  a thin  and 
somewhat  elastic  membrane  which  fills  up  the  whole  of 
this  interval,  and  completes  the  front  and  lateral  parietes 
of  the  Larynx.  Between  this  membrane  and  the  ca- 
vity in  the  base  of  the  Os  Hyoides,  is  a small  sac,  very 
rarely  mentioned  by  anatomists,  and  considered  by  such 
as  speak  of  it,  as  a Bursa  Mucosa.  It  has  no  connex- 
ion with  any  other  cavity,  and  is  occasionally  the  seat 
of  disease.  When  its  natural  secretion  is  converted  in- 
to a meliceris,  it  is  disposed  to  ulcerate,  and  form  a fis- 
tulous sore  in  the  neck,  not  to  be  cured  except  by  ex- 
tirpation. This  remark,  on  its  disease,  I have  got  from 
Dr.  Physick,  in  whose  practice  it  is  not  uncommon; 
latterly,  I have  seen  him  operate  successfully  for  it  in  the 
encysted  state. 

Between  the  Epiglottis  and  the  Thyi’oid  Cartilage. 


THE  LARYNX. 


157 


and  on  the  posterior  face  of  the  Thyreo-hyoid  mem- 
brane, is  a quantity  of  loose  fatty  matter  intermixed 
with  small  mucous  glands ; the  perforations  in  the  Epi- 
glottis are  supposed  to  conduct  the  excretory  tubes  of 
the  latter  into  the  Larynx. 

Between  the  Thyroid  and  Cricoid  cartilages,  in  front, 
there  is  a ligamentous  membrane  which  fills  up  this  in- 
terval 5 it  is  the  Crico-thyroid  membrane,  and  in  Laryn- 
gotomy,  is  indicated  as  the  proper  place  for  the  opera- 
tion. 

From  the  antei’ior  part  of  the  base  of  eaich  Aryte- 
noid cartilage,  a ligament  passes  horizontally  to  the  en- 
tering angle  of  the  Thyroid.  These  ligaments  are  not 
parallel,  but  converge  from  the  Arytenoid  cartilages, 
and  are  very  near  each  other  in  front.  At  the  dis- 
tance of  three  lines  above  these,  are  two  other  ligaments 
passing  also  horizontally  from  the  Arytenoids  to  the  thy- 
roid cartilage;  they  are  more  parallel,  but  have  not 
their  ligamentous  character  so  well  defined. 

There  are  several  pairs  of  muscles  belonging  to  the 
Larynx. 

1.  The  Crico-Thyroideus^  arises  tendinous  and 
fleshy  from  the  anterior  lateral  surface  of  the  cri- 
coid cartilage,  and  passes  upwards  and  backwards, 
to  be  inserted  into  the  inferior  cornu  of  the  thy- 
roid cartilage,  and  the  adjacent  part  of  its  inferior 
edge.  Use,  to  draw  these  cartilages  obliquely  to- 
gether. 


158 


OF  THE  HEAD  AND  NECK. 


2.  TheTHYREO-HvoiDEUs,  which  is  described  in  the 
account  of  the  neck,  page  16. 

3.  The  Cktco-Arytenoideus  Posticus,  arises 
from  the  back  of  the  cricoid  cartilage,  occupying  its 
excavation,  and  is  inserted  into  the  posterior  part  of 
the  base  of  the  arytenoid  cartilage.  To  draw  the 
arytenoid  backwards,  and  make  the  ligaments  tense. 

4.  The  Crico-Arytenoideus  Lateralis,  arises 
from  the  side  of  the  cricoid  cartilage,  and  is  inserted 
into  the  side  of  the  base  of  the  arytenoid.  Use,  to 
draw  this  cartilage  outwards,  and  open  the  eliink  of  the 
glottis. 

5.  The  Thyreo-Arytenoideus,  arises  from  the 
posterior  face  of  the  thyi’oid  cartilage,  and  the  ligament 
connecting  it  with  the  ericoid,  and  is  inserted  into  the 
anterior  edge  of  the  arytenoid  cartilage.  Use,  to  re- 
lax the  ligaments  of  the  glottis. 

6.  The  Arytenoideus  Obliquus,  arises  from  the 
base  of  one  arytenoid  cartilage,  and  is  inserted  into  the 
tip  of  the  other.  It  is  a very  §mall  fasciculus,  and 
sometimes  only  one  muscle  exists.  Use,  to  close  the 
chink  of  the  glottis. 

7.  The  Arytenoideus  Trans  versus,  arises  pos- 
teriorly from  the  whole  length  of  one  arytenoid  carti- 


THE  LARYNX. 


159 


lage,  excepting  a little  part  of  the  tip,  and  is  inserted 
in  a corresponding  manner,  into  the  other.  Use,  to 
close  the  chink  of  the  glottis. 

8.  The  Thyreo-Epiglottideus,  arises  by  a few 
fibres,  from  the  posterior  face  of  the  thyroid  cartilage 
near  its  entering  angle,  and  is  inserted  into  the  side 
of  the  Epiglottis.  Use,  to  draw  the  Epiglottis  down- 
wards. 

9.  The  Aryteno-Epiglottideus,  arises  by  a few 
indistinct  fibres,  from  the  superior  lateral  parts  of  the 
arytenoid  cartilage,  and  is  inserted  into  the  side  of 
the  Epiglottis.  Use,  to.  draw  the  Epiglottis  down- 
wards. 

These  two  last  muscles  are  generally  so  small  and  un- 
defined, that  they  cannot  be  satisfactorily  distinguish- 
ed from  the  adjacent  soft  parts. 

The  cavity  of  the  Larynx  is  lined  by  a continuation 
of  the  mucous  membrane  of  the  Pharynx.  This  mem- 
brane, where  it  establishes  the  upper  boundary  of  the 
Laryngeal  cavity,  forms  a fold  on  each  side,  extending 
from  the  Epiglottis  to  the  Arytenoid  Cartilage ; it  then 
sinks  into  the  cavity  beneath.  In  extending  from  the 
upper  to  the  lower  ligament  of  the  glottis,  on  each 
side,  it  forms  a pouch  between  them,  called  the  ven- 
tricle of  Galen  or  Morgagni.  From  the  lower  ligament 


160 


OF  THE  HEAD  AND  NECK. 


this  membrane  passes  to  line  the  Cricoid  Cartilage, 
aiid  thence  into  the  Trachea. 

The  fissure  between  the  two  lower  ligaments,  is  the 
Rima  Glottidis;  and  the  cavity  above  the  upper  liga- 
ments is  the  Glottis. 

For  an  account  of  the  Trachea,  see  the  article 
Thorax. 

Notwithstanding  the  Epiglottis  is  considered  as  a 
valve  which  shuts  over  the  larynx  in  swallowing  and 
prevents  articles  of  food  from  descending  into  it,  I am 
much  inclined  to  doubt  the  entire  correctness  of  the 
opinion;  for  there  is  no  muscular  apparatus  in  the 
structure  capable  of  producing  tliis  position,  and,  there- 
fore, when  it  does  occur,  it  must  depend  essentially 
on  the  mechanical  pressure  of  the  moi’sel  which  we 
swallow.  But  this  explanation  does  not  account  for  our 
ability  to  swallow  fluids,  or  to  swallow  a very  small 
body,  as  a crumb  of  bread ; neither  does  it  account  for 
the  manner  in  which  the  larynx  is  protected  in  vomit- 
ing. It  is  more  than  probable  that  in  all  these  acts, 
the  motion  of  the  larynx  is  the  same. 

Always  impressed  with  the  insufficiency  of  these 
doctrines,  and  knowing  also  that  they  had  been  render- 
ed still  more  questionable  by  cases  in  which  the  uppei 
part  of  the  epiglottis  had  been  lost  by  wounds  or  ulce- 
ration,^' I remained  unsatisfied  till  very  lately.  In  the 

* I have  now  a case  of  this  kind  in  the  A.  H.  Infirmary. 


I LARYNX.  161 

spring  of  1822,  in  dissecting  a muscular  subject,  I had 
occasion  to  observe  a position  of  these  parts  whic  h will 
account  for  all.  The  upper  part  of  the  glottis  was 
closed,  but  in  a manner  precisely  the  reverse  of  the 
received  opinion ; the  epiglottis,  instead  of  being 
drawn  down  over  this  opening,  had  the  opening  drawn 
up  to  it.  The  natural  position  of  the  epiglottis,  is  not 
vertical,  but  somewhat  obliquely  backwards.  Consider- 
ing the  upper  opening  of  the  larynx  as  constituted  by 
a plane  passing  from  the  tip  of  the  arytenoid  cartilages 
along  the  superior  line  of  the  cricoid  cartilage,  we  shall 
then  have  a surface  which  by  being  brought  some  what 
obliquely  forwards,  will  come  in  contact  with  or  nearly 
so,  and  be  parallel  to  the  posterior  face,  of  the  epi- 
glottis, while  the  latter  is  in  its  natural  position.  It  is, 
I believe,  in  this  manner  that  the  upper  opening  of 
the  windpipe  is  closed,  nor  are  we  deficient  in  pointing 
out  the  agent. 

By  examining  the  position  and  strength  of  the  thyreo 
hyoid  muscle  it  will  be  obvious  that  the  shortening  of  the 
larynx,  which  this  muscle  is  said  to  produce,  ^s,  in  a 
strict  analysis  of  it,  no  other  motion  than  what  I have 
just  described.  It  is  probable  that  the  inferior  con- 
strictor of  the  pharynx  concurs  in  the  same  motion, 
particularly  its  upper  fibres.  The  stylo-pharyngeus 
does  the  same,  and  is.  very  favourably  inserted  into  the 
posterior  margin  of  the  thyroid  cartilage.  If  the 
glottis  be  protected  in  this  way  during  deglutition  it 
shows  satisfactorily  why  the  soldier,  mentioned  by 


X 


162 


OF  THE  HEAD  AND  NECK. 


Larrey,  whose  epiglottis  was  cut  off  by  a musket  ball, 
when  the  wound  cicatrized,  could  swallow  as  well  as 
usual,  and  why  such  as  have  the  upper  part  of  the 
epiglottis  cartilage  removed  by  venereal  ulceration  suf- 
fer no  inconvenience  of  consequence  from  it. 


PART  II. 


OF  THE  TRUNK. 


CHAPTER  L 
Of  the  Thorax. 

The  dissection  of  the  cavity  of  the  Thorax  should  be 
preceded  by  that  of  the  muscles  which  lie  upon  its 
front  part  and  sides. 


Section  I. 

Of  the  Muscles. 

1.  The  Pectoralis  Major  is  the  most  superficial, 
and  forms  the  large  swelling  cushion  of  flesh  under 
the  skin  of  the  breast.  It  arises  tendinous  from  the  an- 
terior face  of  the  two  upper  bones  of  the  sternum  their 


164 


OP  THE  TRUNK. 


whole  length,  fleshy  from  the  cartilages  of  the  fifth  and 
sixth  ribs,  and  by  a fleshy  slip  from  the  upper  part  of 
the  tendon  of  the  external  oblique  muscle.  It  arises 
also  fleshy  from  the  interior  two -thirds  of  the  clavicle. 
The  clavicular  and  sternal  portions  of  the  origin  are 
separated  by  an  interval,  giving  the  appearance  of  two 
muscles. 

The  fibres  converge  and  terminate  by  a broad,  thin 
tendon,  which  is  inserted  into  a roughness  on  the  ex- 
terior edge  of  the  fossa  of  the  os  humeri  for  the  biceps 
tendon.  The  under  edge  of  the  muscle,  near  its  inser- 
tion, is  folded  inwards,  which  gives  the  rounded  thick 
margin  to  the  fore  part  of  the  axilla.  That  part  of  the 
broad  tendon  belonging  to  the  cla\dcular  portion  of  the 
muscle  is  inserted  lower  down  than  the  sternal,  which 
produces  a decussation  of  the  fibres  of  the  tendon. 

The  Petoralis  Major  moves  the  arm  upwards  and  in- 
wards. 

2.  The  Pectop.alis  Minor  is  brought  into  \dew  by 
raising  the  last  muscle.  -,It  is  comparatively  small  and 
somewhat  triangular,  arising  by  thin  tendinous  digita- 
tions  from  the  upper  edges  of  the  third,  fourth,  and 
fifth  ribs.  It  soon  becomes  fleshy,  and  is  inserted,  by 
a short  flat  tendon,  into  the  inner  facette  of  the  coracoid 
process  of  the  scapula.  Its  use  is  to  draw  the  scapula 
inwards  and  downward^. 


3.  TheSuBCLAVius  is  a small  muscle  placed  imme 


MUSCLES  OF  THE  THORAX. 


165 


diately  under  the  clavicle,  arising  from  the  cartilage  of 
the  first  rib,  and  inserted  into  the  inferior  face  of  the 
clavicle  from  near  the  sternum  to  the  conoid  ligament, 
which  connects  the  coracoid  process  and  the  clavicle 
together.  It  draws  the  clavicle  downwards. 

4.  The  Serratus  Major  Axticu^s  is  a broad  mus- 
cle lying  on  the  sides  of  the  ribs,  between  tliem  and 
the  scapula,  and  arising  fi’Oin  a line  anterior  to  their 
middle.  In  well  defined  bones  the  precise  points  of 
origin  are  readily  seen.  It  arises  from  the  nine  upper 
ribs  by  fleshy  digitations,  the  superior  one  of  which 
seems  almost  like  a distinct  muscle,  the  five  lower  are 
connected  to  the  obliquus  externus  abdominis,  the  digi- 
tations of  the  two  muscles  interlocking  with  each  other. 
The  fibres  converge,  and  are  inserted  into  the  base  of 
the  scapula  its  whole  length.  Its  action  is  to  draw  the 
scapula  forwards. 

5.  The  Intercostales  fill  up  the  spaces  between 
the  ribs.  There  are  two  in  each  space.  The  Exter- 
nal arises  from  the  spine  and  from  the  inferior  acute 
edge  of  each  rib  almost  to  its  cartilage,  and  is  inserted 
into  the  superior  rounded  edge  of  the  rib  below  for  the 
same  distance,  its  fibres  passing  obliquely  forwards. 
The  Internal  Intercostal,  arises  from  the  inferior  edge 
of  the  rib,  beginning  at  the  sternum,  and  going  back- 
wards to  the  angle  of  the  rib,  it  is  inserted  into  the 
superior  rounded  edge  of  the  rib  below  on  its  inner 


166 


OF  THE  TRUNK. 


side,  its  fibres  passing  obliquely  backwards.  They 
draw  the  ribs  together. 

With  a view  to  examine  the  cavity  of  the  thorax,  the 
sternum  along  with  the  cartilages  of  the  ribs,  is  to  be 
taken  out.  We  then  see,  on  their  posterior  faces,  a 
muscle  called 

6,  Triangularis  Sterni,  which  arises  from  the 
whole  length  of  the  cartilage  ensiformis  at  its  edge, 
and  from  the  inferior  half  of  the  edge  of  the  second 
bone  of  the  sternum.  The  fibres  go  obliquely  upwards 
and  outwards  to  be  inserted  into  the  cartilages  of  the 
third,  fourth,  fifth  and  sixth  ribs  by  fleshy  and  tendi- 
nous digitations.  Its  use  is  to  depress  the  ribs,  and  con- 
sequently to  diminish  the  cavity  of  the  thorax. 


Section  II. 

Vistet'u  of  the  Thorax. 

The  most  usual  manner  of  getting  into  the  ca\dty  of 
the  Thorax  is  that  just  mentioned ; but  there  is  a much 
better  one  introduced  here,  by  the  late  Professor  Wis- 
TAR,  iu  which  the  five  middle  true  ribs  on  each  side 
are  removed,  all  the  rest  with  the  sternum  being  left. 


VISCERA  OF  THE  THORAX. 


167 


This  plan  gives  an  excellent  view  of  the  several  viscera, 
and  also  of  their  relative  situation  and  extent;  and  it  is 
such  as  I would  recommend  the  student  to  adopt,  in  at 
least  one  dissection.  The  principal  objection  to  it  is, 
that  it  renders  the  upper  parts  of  the  trunk  unfit  for 
farther  investigation,  inasmuch  as  the  superior  extremi- 
ties must  be  removed  in  the  first  place.  If  the  muscles 
connecting  the  upper  extremities  to  the  trunk,  on  its 
fore  and  back  parts,  should  have  been  previously  dis- 
sected, this  objection  is  no  longer  valid. 

Approaching  the  cavity  of  the  thorax,  by  either  of 
the  methods  mentioned,  we  see  at  once  its  most  striking 
contents,  viz.  the  Heart  and  Lungs,  each  covered  by 
an  appropriate  membrane.  The  heart  is  between  the 
sternum  and  the  dorsal  vertebrae ; the  lungs  are  on  each 
side  of  it  and  when  in  a healthy  state,  always  collapse 
upon  the  thorax  being  opened. 

The  Pleurse. 

Each  of  the  two  lungs  has  an  appropriate  membrane 
called  Pleura;  which  covers  its  external  surface;  and 
giving  it  a glistening  smooth  appearance,  is  reflected 
from  the  internal  face  of  the  lung  over  the  proper 
membrane  of  the  heart  to  the  sternum  before,  and  to 
the  spine  behind.  The  membrane  also  lines  the  ribs, 
intercostal  muscles  and  diaphragm,  of  that  side  of  the 
thorax  to  which  it  belongs.  Above,  it  passes  up  as 
high  as  the  head  of  the  first  rib,  and  below,  it  goes  as 


168 


OF  THE  TRUNK. 


low  down,  as  the  last  rib.  That  part  of  the  plem-a 
which  covers  the  lung,  is  the  Pleura  Pulinonalis,  and 
that  Vi^hich  lines  the  ribs,  the  Pleura  Costalis. 

As  the  pleurae  are  bags,  one  on  each  side  of  the 
thorax,  it  is  very  demonstrable  that  the  contiguous  faces 
of  them  form  a septum,  which  extends  from  the  stei'* 
niim  in  front  to  the  spine  behind,  and  from  the  upper 
part  of  the  thorax  to  the  diaphragm.  This  septum  is 
the  Mediastinum ; and  the  heart  is  placed  in  its  middle. 
The  portion  of  the  septum  between  the  heart  and  ster- 
num is  the  Anterior  Mediastinum ; between  the  heart 
and  spine  is  the  Posterior  Mediastinum ; and  between 
the  heart  and  the  upper  part  of  the  thorax,  is  the 
Superior  Mediastinum ; each  of  which  merits  strict  at- 
tention. 

It  is  obvious  then,  that  the  septum  consists  of  two 
laminae,  one  from  each  pleura.  These  two  laminae 
are  somewhat  separated, . where  they  are  called  Ante- 
rior Mediastinum,  by  tlie  remains  of  the  thymus  gland 
above,  and  by  adipose  and  cellular  membrane  below. 
The  anterior  mediastinum  is  attached  to  the  middle  of 
the  sternum,  except  at  its  lower  part,  where  it  inclines 
somewhat  to  the  left, side.  . To  get  a good  view  of  its 
contents,  the  stfernum  must  be  s^ved  through  longitu- 
dinally, and  the  two  halves  separated  an  inch  by  a 
small  block  of  wood.  The  contents  of  the  posterior  me- 
diastinum and  of  the  superior,  are  best  seen  and  under- 
stood at  a subsequent  stage  of  the  dissection. 

The  Pleura  is  a thin  and  transparent  membrane  coji 


VISCERA  OF  THE  THORAX, 


169 


nected  to  the  parts  on  which  it  lies  by  a short  cellular 
substance.  No  red  vessels,  in  its  healthy  state,  are  to 
be  observed.  In  the  young  subject,  it  is  free  from 
adeps;  but  in  advanced  life,  attended  with  corpulency, 
considerable  masses  of  fat  are  found  in  the  anterior  me- 
diastinum, and  between  it  and  the  pericardium.  The 
exhalent  vessels  of  the  pleura  are  derived  from  the  in- 
tercostal, internal  mammary,  phrenic,  and  some  other 
arteries,  and  secrete  a fluid  which  lubricates  its  surface. 

The  Pericardium. 

Between  the  pleurae,  and  under  the  sternum,  is  the 
Pericardium,  containing  the  heart.  It  is  a white,  semi- 
transparent membrane,  of  a condensed  fibrous  structure, 
possessed  of  little  or  no  elasticity,  which  renders  it 
highly  appropriate  for  sustaining  the  action  of  the 
heart  in  its  dilatation. 

It  is  a complete  sac,  consisting  of  two  laminae;  and 
is  reflected  over  the  surface  of  the  heart,  so  as  to  give 
it  an  investing  membrane.  This  investment  commen- 
ces at  the  back  part  or  base  of  the  heart,  and  is  conti- 
nued over  the  whole  of  it,  being  extended  on  the  aorta 
to  the  branches  which  arise  from  the  top  of  its  curva- 
ture; on  the  pulmonary  artery  to  its  bifurcation;  on  the 
pulmonary  veins  to  their  first  branches;  on  the  ascend- 
ing cava  to  the  diaphragm;  and  on  the  descending  cava 
to  the  middle  of  the  space  between  the  entrance  of  the 
Vena  Azygos  and  the  Transverse  Vein.  The  exterior 

Y 


170 


OF  THE  TRUNK. 


lamina  has  not  these  reflections,  it  is  only  united  to  the 
several  parts  where  the  reflections  commence. 

An  analogy  is  observable  in  this  arrangement  with 
the  membranes  of  the  joints;  the  exterior  lamina  of  the 
pericardium  corresponds  with  the  capsular  ligament, 
and  the  internal  lamina  with  the  synovial  membrane. 
It  is  the  exterior  membrane  which  supports  the  heart, 
and  the  interior  which  furnishes  the  lubricating  fluid, 
found  in  general  in  the  pericardium,  to  the  amount  of  a 
drachm.  The  anterior  part  of  the  pericardium  lies 
loosely  on  the  heart.  The  pericardium  is  attached 
strongly,  by  all  its  inferior  surface,  to  the  tendon  of 
the  diaphragm. 


The  Heart. 

The  Heart  is  a hollow  muscle  consisting  of  four  cavi 
ties,  two  auricles,  and  two  ventricles.  Its  shape  is  some- 
what conical,  but  flattened  on  the  under  surface.  The 
base  of  the  cone  is  formed  by  the  auricles,  the  body  by 
the  ventricles,  and  the  apex  by  the  point  of  the  left 
ventricle  projecting  beyond  that  of  the  other.  The 
heart  being  fixed  as  mentioned  between  the  sternum 
and  the  dorsal  vertebrae,  has  its  base  turned  obliquely 
towards  the  right  side,  while  its  apex  is  about  the  junc- 
tion of  the  fifth  rib  with  its  cartilage,  on  the  left.  Its 
flat  part  reposes  on  the  flat  tendon  in  the  centre  of  the 
diaphragm,  also  is  on  a horizontal  line,  or  nearly  so, 
with  the  inferior  end  of  the  second  bone  of  the  sternum, 


VISCERA  OF  THE  THORAX. 


171 


'fhe  heart,  in  consequence  of  being  tied  down  to  the 
diaphragm  by  the  pericardium,  is,  excepting  its  pulsa- 
tions, exposed  to  but  little  motion,  and  is  therefore 
almost  uniformly  in  the  same  position.  It  has,  between 
the  internal  membrane  of  the  pericardium  and  its  own 
substance,  more  particularly  along  the  course  of  the  co- 
ronary vessels,  adipose  matter  in  great  abundance  in 
old  subjects,  and  this  adipose  matter  sometimes  pene- 
trates so  deeply  between  the  fasciculi  of  its  fibres  as  to 
give  them  a very  loose  texture,  and  apparently  to  dis- 
qualify them  in  some  measure  from  performing  their 
functions. 

The  parietes  of  the  heart  are  formed  principally  of 
muscular  fibres,  which  are  variously  arranged ; some 
pass  spirally  around  it,  others  in  an  irregular  and 
indeterminate  manner,  but  all  in  such  a direction 
as  to  concur,  by  contracting,  in  effacing  its  cavities. 
The  cavities  are  lined  by  a smooth  elastic  membrane 
which  is  a continuation  of,  and  resembles  the  internal 
coat  of  the  arteries  and  veins.  Between  the  auricles 
and  ventricles,  and  at  the  orifices  of  the  great  arteries, 
this  membrane  is  raised  up  and  reflected  so  as  to  con- 
stitute valves. 

The  heart  is  divided  into  Right  and  Left  sides,  each 
consisting  of  an  auricle  and  of  a ventricle.  The  Right 
Auricle  receives  the  two  great  trunks  of  the  Venous 
System,  to  wit,  the  ascending  and  the  descending  Vena 
Cava.  The  Left  Auricle  receives  the  pulmonary  veins. 


172 


OF  THE  TRUNK. 


The  Right  Ventricle  sends  off  the  Pulmonary  Artery, 
and  the  Left  Ventricle  the  Aorta. 

The  Right  Auricle,  situated  at  the  right  posterior- 
part  of  the  heart,  is  an  oblong  cavity  about  a line  in 
thickness.  To  view  its  internal  arrangement  it  should 
be  slit  open  in  front  from  cava  to  cava,  we  shall  then  see 
that  its  posterior  surface  is  smooth  and  is  formed  by  a 
continuation  of  the  structure  of  the  great  veins  which 
meet  each  other  at  an  obtuse  angle,  and  form  a projec- 
tion into  the  auricles.  This  last  circumstance,  connect- 
ed with  a slight  thickening  of  the  part,  has  given  oc- 
casion to  the  name  Tuberculum  Loweri.  Anteriorly 
the  auricle  is  swelled  into  a pouch,  (Sinus  Venosus) 
in  which  the  muscular  fibres,  instead  of  being  uni- 
formly spread  into  a coat,  are  collected  into  fasciculi 
lying  parallel  to  and  near  each  other ; they  are  called 
Musculi  Pectinati.  At  the  upper  part  of  the  pouch  or 
sinus  is  the  proper  auricular  portion  of  the  caAnty, 
whence  it  got  its  name ; it  is  not  marked  by  any  pecu- 
liarity except  that  the  musculi  pectinati  prevail  in  it. 
Theaui’icles  have  a common  septum,  and  on  it,  just  below 
the  tuberculum  loweri,  is  situated  the  F ossa  Ovalis,  which 
in  the  foetal  state  was  an  opening  between  the  auricles, 
and  indeed  at  the  upper  part  of  this  depression  we 
often  find  a foramen  large  enough  to  admit  a probe 
into  the  left  auricle,  even  in  subjects  advanced  into 
old  age.  The  edges  of  the  fossa  ovalis,  are  elevated 


VISCERA  OF  THE  THORAX. 


173 


and  thickened,  being  the  Columnse  or  Annulus  Fossse 
Ovalis. 

Beneath  the  fossa  ovalis  is  the  Eustachian  valve.  It 
is  formed  by  a duplicature  of  the  lining  membrane  of 
the  auricle  and  of  the  ascending  cava,  being  spread 
somewhat  obliquely  across  the  orifice  of  the  latter.  It 
is  of  a crescentic  shape,  about  half  an  inch  wide,  but 
occasionally  reticulated,  and  commences  at  the  left 
pillar  of  the  annulus  ovalis;  it  terminates  anteriorly 
about  the  junction  of  the  auricle  and  the  vein.  It  is 
connected  by  its  convex  edge  to  the  parietes  of  the  au- 
ricle, and  its  concave  or  floating  edge  looks  somewhat 
upwards.  Just  before  and  below  the  Eustachian  valve 
is  another  much  smaller,  but  also  semilunated,  which 
covers  the  orifice  of  the  coronary  vein. 

At  the  left  side  of  the  right  auricle  is  an  opening  of 
more  than  an  inch  in  diameter,  the  Ostium  Venosum, 
through  which  it  communicates  with  the  right  ven- 
tricle. 

In  the  right  auricle  are  many  small  orifices  of  coro- 
nary veins  called  Foramina  Thebesii;  they  also  exist 
in  all  the  other  cavities,  but  are  not  so  numerous 
there.  They  are  said  to  be  particularly  conspicuous  in 
cases  of  diseased  lungs. 

The  next  ca^uty  to  be  examined  is  the  Right  Ventri- 
cle ; to  expose  it  satisfactorily  it  should  be  divided  ex- 
tensively along  the  septum  ventriculorum  superiorly 
and  inferiorly.  It  is  of  a triangular  form,  and  its  sides 


174 


OF  THE  TRUNK. 


are  much  thicker  than  the  sides  of  the  auricle,  as  they 
measure,  most  commonly,  about  three  lines.  Its  inter- 
nal surface  is  very  irregular  and  rough,  the  muscular 
structure  of  it  being  thrown  into  projecting  columns  of 
very  indeterminate  figures,  arrangement  and  dimen- 
sions. Some  of  them  jut  out,  and  are  connected  to  the 
valves  at  the  ostium  venosum  by  intermediate  tendons ; 
others  pass  from  one  side  of  the  ventricle  to  the  other 
and  a third  series  presents  a reticulated  appearance, 
lying  on  the  face  of  the  ventricle  and  connected  with  it. 
Their  general  object  is  to  strengthen  the  ventricle,  to 
enable  it  to  expel  its  contents  and  to  agitate  well  and 
mix  the  blood. 

The  Ostium  Venosum  has  a tendinous  margin,  fi’om 
which  is  reflected  the  lining  membrane  of  the  ventri- 
cle, so  as  to  form  a broad  fold  surrounding  it.  This  fold 
being  eight  or  ten  lines  wide,  is  irregularly  divided  at 
its  floating  edge,  into  three  parts,  whence  the  name  of 
Tricuspid  Valve  has  been  given  to  it.  The  tricuspid 
valve,  is  situated  in  the  ventricle^  has  its  loose  margin 
attached  to  the  round  tendinous  chords  just  mentioned, 
called  the  Chordae  Tendineae,  which  again  arise  from 
the  Columnae  Carneae.  These  tendinous  attachments  of 
the  tricuspid  valves  prevent  them  from  being  thrown 
into  the  auricle  when  the  ventricle  contracts. 

At  the  upper  part  of  the  ventricle  is  the  orifice  of 
the  pulmonary  artery,  which  conveys  the  blood  to  the 
lungs ; provision  for  it  is  made  by  the  upper  part  of 


VISCERA  OF  THE  THORAX. 


175 


the  ventricle  becoming  smooth.  The  orifice  of  the 
artery  is  round,  and  about  twelve  lines  in  diameter. 
From  the  internal  surface  of  the  artery,  a little  beyond 
its  orifice,  three  valves  arise  called  Semilunar,  which 
may  be  compared,  each  to  a semicircular  plane,  con- 
nected by  its  circumference,  to  a cylindrical  cavity. 
The  diameter  of  the  plane  is  loose ; in  the  centre  of  it, 
is  a small  cartilaginous  body,  the  Corpusculum  Aurantii; 
and  on  each  side  of  the  corpusculum,  the  diameter  of 
the  valve,  instead  of  being  a straight  line,  is  slightly  fes- 
tooned. The  valve  is  almost  diaphanous,  and  seems  to 
be  produced  by  a reflection  of  the  lining  membrane  of 
the  artery.  Between  the  coats  of  this  reflection  is  how- 
ever, to  be  found  another  substance  very  much  like  that 
of  the  artery,  which  also  forms  a festooned  edge  a little 
below  the  one  just  described.  As  the  three  valves  are 
placed  in  a row  surrounding  the  artery,  in  its  action 
they  are  thrown  down,  forming  thereby  a complete 
septum  against  the  return  of  the  blood  into  the  ven- 
tricle ; and  the  Corpuscula  Aurantii  being  in  the  mid- 
dle of  each  form  a point  d’appui  or  abutment  at  which 
the  edges  of  the  valves  support  each  other.  Between 
the  outer  face  of  the  valve  and  the  internal  face  of  the 
artery,  a pocket  attended  with  a dilatation  of  the  artery 
is  formed,  called  the  Sinus  of  Valsalva. 

The  Pulmonary  Artery  is  a large  white  fibrous 
tube  given  off*  in  the  manner  mentioned ; under  the 
arch  of  the  aorta,  it  divides  into  two  branches  of  nearlv 


176 


OF  THE  TRUNK. 


equal  magnitude,  right  and  left,  which  go  to  the  lungs 
of  their  respective  sides.  The  right  branch  passes  un- 
der the  arch,  and  is  then  minutely  distributed  to  the 
lung.  The  left  is  in  front  of  the  descending  aorta, 
and  is  distributed  to  the  left  lung  with  equal  minute- 
ness. 

The  blood  is  brought  from  the  lungs  by  the  pulmo- 
nary veins,  which  are  four  in  number,  two  on  each 
side.  The  branches  constituting  the  trunk  of  each  of 
these  veins,  are  generally  united  before  the  trunk  pene- 
trates the  pericardium.  This  trunk  afterwards  unites 
to  the  auricle  at  one  of  its  corners. 

The  Left  Auricle  has  about  the  same  cubic  capacity 
with  the  right,  but  differs  from  it  somewhat  in  its 
figure,  by  being  more  square.  Its  broad  internal  sur- 
face looks  towards  the  spine.  It  is  fixed  to  the  pos- 
terior part  of  tlie  left  ventricle,  and  is  divided  like  the 
right  auricle,  into  the  Sinus  Venosus,  sometimes  called 
Sinus  Pulmonalis,  and  into  Proper  Auricle.  The  lat- 
ter is  situated  at  the  left  side  of  the  pulmonary  artery, 
and  is  somewhat  longer,  narrower,  more  crooked,  and 
more  notched  at  its  margins  than  the  other  proper 
auricle.  When  the  left  auricle  is  cut  open,  whicli 
should  be  done  by  a slit  down  its  middle,  it  will  be  per- 
ceived that  its  parietes  are  thicker  than  those  of  the 
right,  and  that  both  externally  and  internally,  its  sur- 
faces are  perfectly  smooth,  except  in  the  proper  auri- 
cular part,  where  the  Musculi  Pectiiiati  prevail. 


TISCERA  OF  THE  THORAX 


17? 


The  Septum  between  the  auricles,  viewed  on  this 
side,  is  smooth,  not  presenting  any  remarkable  appear- 
ance ; when  held  up  to  the  light,  it  is  seen  to  be  thinner 
and  more  transparent  at  the  place  corresponding  with 
the  fossa  ovalis  of  the  other  side.  At  the  anterior  and 
inferior  side  of  the  auricle  is  the  ostium  venosum,  com- 
municating with  the  left  ventricle ; it  has  a tendinous 
margin,  and  is  rather  more  than  an  inch  in  diameter. 

The  Left  Ventricle  differs  from  the  right  in  shape,  by 
being  more  conical,  but  it  is  equally  capacious. , Its  an- 
terior part  constitutes  the  apex  of  the  heart,  and  strikes 
against  the  ribs.  The  best  mode  of  examining  its 
cavity  is  to  make  an  incision  through  its  parietes  near 
the  septum,  and  to  separate  it  completely  on  that  side 
from  its  fellow.  Another  incision  should  be  made  so  as 
to  detach  it  from  the  auricle,  also,  near  their  septum. 
The  latter  cut  is  to  be  executed  with  particular  care,  so 
as  to  avoid  wounding  the  interior  structure.  That 
done,  we  see  its  general  arrangement  within,  corres- 
ponding with  the  right  ventricle.  Its  parietes  are 
eight  lines  through,  being  about  three  times  as  thick  as 
the  other.  Its  columnse  carnese  are  larger  and  stronger, 
but  arranged  on  the  same  principle,  some  passing  from 
side  to  side  of  the  cavity,  others  being  reticulated  and 
easily  raised  up  from  the  part  of  the  ventricle  on 
which  they  lie,  and  a third  set  aiding  the  valvular  ap- 
paratus at  the  ostium  venosum. 

The  Mitral  Valve  exists  at  the  left  ostium  venosum, 

z 


178 


OF  THE  TRUNK. 


and  is  formed  by  a duplicature  of  the  lining  membrane 
of  the  ventricle.  It  is  partially  divided  into  two  parts, 
which  are  pointed  at  their  edges.  Its  columnas  car- 
nese  are  numerous  and  strong,  and  its  chordse  tendiueae 
are  of  corresponding  characters.  The  mitral  valve 
prevents  the  regurgitation  of  blood  into  the  auricle, 
and  is  so  placed  that  the  upper  half  of  it,  when  the 
blood  is  rushing  into  the  ventricle,  conceals  the  orifice 
of  the  aorta. 

Towards  the  orifice  of  the  aorta,  which  is  at  the 
posterior  superior  part  of  the  ventricle,  the  surface  of 
this  cavity  is  smooth  to  facilitate  the  passage  of  blood. 
The  septum  between  the  ventricles  is  of  the  same 
thickness  with  the  left  ventricle;  it  is  formed  partly  by 
the  right  ventricle,  but  principally  by  the  left. 

The  Mouth  of  the  Aorta  is  about  an  inch  in  diame- 
ter, and  is  furnished  with  three  Semilunar  Valves, 
Corpuscula  Aurantii,  and  Sinuses  of  Valsalva,  after  the 
same  manner  with  the  pulmonary  artery,  so  that  the 
description  of  one  will  suit  the  other  with  the  addition 
that  those  parts  of  the  aorta  are  stronger  and  more 
developed.  The  coats  of  the  aorta  are  nearly  three 
times  as  thick  as  those  of  the  pulmonary  artery,  to 
qualify  it  for  bearing  the  increased  pressure  of  the 
blood.  At  the  upper  part  of  its  curvature  the  aorta 
is  dilated,  to  form  the  large  Sinus  of  Valsalva.  The 
aorta  lies  first  at  the  back  of  the  pulmonary  artei’y, 
it  then  gets  to  its  right,  being  between  it  and  the 


VISCERA  OF  THE  THORAX. 


179 


superior  vena  cava;  part  of  it  is  there  to  the  right  of 
the  spine,  it  then  makes  its  arch  which  brings  it  to 
the  left  of  the  spine  and  in  contact  with  it  about  the 
third  dorsal  vertebra.  The  superior  part  of  its  arch 
is  about  eight  lines  below  the  upper  edge  of  the  ster- 
num. 

The  heart  being  a mere  machine  for  propelling 
blood,  requires  another  source  for  its  nourishment  be- 
sides the  fluid  circulating  through  its  great  cavities; 
this  is  furnished  by  the  Coronary  Arteries,  which  are 
two  in  number.  The  first,  called  Right  Coronary,  be- 
comes visible  between  the  pulmonary  artery  and  the 
right  auricle,  and  passing  on  the  septum  between  the 
right  auricle  and  ventricle,  extends  around  the  heart  to 
its  flat  side,  distributing  to  the  contiguous  parts 
branches  which,  for  the  most  part,  pass  oft*  at  right 
angles.  The  second,  or  Left  Coronary  Artery  appears 
between  the  pulmonary  artery  and  the  left  auricle; 
before  it  has  become  very  obvious,  it  divides  into  two 
branches,  one  passes  on  the  septum  ventriculorura  to 
the  apex  of  the  heart;  the  other  winds  on  the  septum 
between  the  left  auricle  and  the  left  ventricle,  and 
some  of  its  branches  pass  on  the  flat  surface  of  the 
heart  to  its  apex. 

The  Coronary  Veins  receree  the  blood  of  the  coro- 
nary arteries;  a common  trunk  is  formed  by  them, 
which  passes  for  some  distance  on  the  septum,  between 
the  left  auricle  and  ventricle,  and  then  opens  into  tl^e 


180 


UF  THE  TRUNK. 


right  auricle  just  anterior  to  the  Eustachian  Valve,  at 
the  spot  already  indicated. 

Of  the.  Lungs. 

The  Lungs  occupy,  by  far,  the  greater  part  of  the 
cavity  of  the  thorax,  and  consist  of  two  distinct  bodies 
placed  one  at  either  side  of  the  heart,  from  which  cir- 
cumstance they  are  called  right  and  left  Lung.  Their 
external  shape  and  dimensions,  with  an  inconsiderable 
exception,  are  the  same,  as  they  correspond  in  their 
periphery  with  the  symmetrical  sides  of  the  thorax. 
The  apex  of  the  heart,  from  bein^  pushed  into  the  lung 
of  the  left  side,  gives  its  surface  towards  the  mediasti- 
num, a somewhat  different  figure  from  the  lung  of  the 
right  side. 

Each  lung  is  divided  by  deep  fissures  into  lobes ; the 
right  lung  has  three  lobes,  the  left  two.  To  appreciate 
the  extent  and  form  of  the  lung,  it  must  be  recollected 
that  the  cavity  of  the  thorax  is  much  deeper  behind 
than  it  is  before.  The  vertical  diameter  before, 
amounts  only  to  the  length  of  the  two  upper  bones  of 
the  sternum,  whereas  the  same  diameter  behind,  is  the 
whole  length  of  the  column  formed  by  the  doi’sal  verte- 
brse.  The  figure  of  each  lung  is  also  modified  by  the 
convexity  of  the  Diaphragm ; for  this  body,  extending 
from  the  lower  point  of  the  dorsal  vertebrae  obliquely 
upwards  to  the  end  of  the  second  bone  of  the  sternum, 
would,  if  it  were  only  a plain  surface,  influence  the  con 


VISCERA  OF  THE  THORAX. 


181 


tigiious  faces  of  the  lungs  so  as  to  make  them  resemble^ 
when  united,  the  inferior  part  of  an  ox’s  hoof;  but  this 
1‘esemblance  is  much  increased  by  the  diaphragm  form- 
ing a convexity  towards  the  thorax,  which  rises  much 
above  what  its  plane  wmiild.  The  similitude  of  the 
lungs  to  the  ox’s  hoof,  with  the  back  part  foremost,  is 
therefore  sufficiently  exact  for  anatomical  comparison, 
and  particularly  as  it  regards  their  inferior  surface. 

The  lung  lies  loose  every  where,  except  at  the  sur- 
face corresponding  to  the  side  of  the  basis  of  the  heart; 
here  it  is  attached  to  the  heart  by  the  pulmonary  veins, 
pulmonary  artery,  and  by  a branch  of  the  trachea. 
These  tubes  constitute  the  Root  of  the  Lung,  and  over 
the  root  is  reflected  the  pleura  from  the  pericardium. 
The  pleura  which  covers  the  root  of  the  lung  is  ex- 
tended downwards,  under  the  name  of  Ligamentum 
Pulmonis,  and  serves  to  fix  the  posterior  edge  of  the 
lung  to  the  pericardium,  as  low  down  as  the  diaphragm. 

The  structure  of  the  lung  is  of  extreme  delicacy. 
It  consists  of  small  cells  which  are  the  ultimate  ter- 
minations of  the  bronchium.  The  Bronchium  may  be 
compared  to  the  stalk  of  a bunch  of  grapes,  and  the 
cells  of  the  lungs  to  the  fruit;  each  grape,  which  is 
the  cell,  adhering  to  its  pedicle  or  stem,  which  is  a 
ramification  of  the  Bronchium.  On  these  cells  the 
pulmonary  artery  and  vein  ramify  very  minutely,  for 
the  purpose  of  airing  the  blood.  These  cells  are  in 
contact  one  with  the  other,  and  are  kept  together  by 


182 


OF  THE  TRUNK. 


common  cellular  membrane,  such  as  forms  the  medium 
of  connexion  for  other  parts  of  the  body.  The  lung 
of  the  bullock  exhibits  this  structure  better  than  that  of' 
the  human  lung,  and  in  it  we  also  see,  by  a little  tear- 
ing of  the  parts  asunder,  the  manner  in  which  each 
lobe  is  divided  into  Lobuli  or  smaller  lobes,  which  again 
are  constituted  by  the  cells  of  the  lung.  These  lobuli 
are  well  seen  in  the  foetus,  and  in  very  young  subjects. 

The  Trachea,  the  bifurcation  of  which  forms  the 
Bronchia  is  a tube  almost  cylindrical,  which  passes  in 
front  of  the  oesophagus  and  of  the  vertebrae,  from  the  in- 
ferior part  of  the  larynx  to  the  third  dorsal  vertebra ; it 
there  divides  into  the  Bronchia,  and  is  placed  between 
pleurae  of  the  two  sides  of  the  thorax.  The  right 
Bronchium  is  shorter,  larger,  and  less  slanting  than 
the  left;  it  sinks  below  the  pulmonary  artery,  and 
penetrates  the  lung  opposite  to  the  fourth  doi*sal  ver- 
tebra ; the  left  being  long  and  nari’ow,  enters  the  lung 
below  the  pulmonary  artery,  opposite  to  the  fifth  dor- 
sal vertebra.  The  Bronchia  then  divide  and  sub- 
divide through  the  structure  of  the  lung,  till  the 
ultimate  extremities  of  the  tube  terminate  in  the  aii' 
cells. 

The  trachea  preserves  its  cylindrical  shape,  and 
is  kept  open  by  a cartilaginous  structure,  which  is  com- 
posed of  from  sixteen  to  twenty  pieces,  more  or  less 
distinct  from  each  other:  some  are  separated  entirely: 
some  are  united  to  the  contiguous  ones  by  their  middle. 


VISCERxi  OF  THE  THORAX. 


183 


and  others  by  their  extremities.  Thus  arranged,  the 
cartilages  form  about  two  thirds  of  the  circumference 
of  a circle,  occupying  the  front  of  the  trachea,  and  giv- 
ing it  the  appearance,  anteriorly,  of  a cartilaginous 
tube.  The  remaining  third  is  membranous.  The  car- 
tilages of  the  trachea  are  deposited  in  a kind  of  peri- 
chondrium, possessed  of  extreme  elasticity,  which  has 
continually  a tendency  to  approximate  the  cartilages,  and 
is  resisted  only  by  the  attachments  of  the  two  extremi- 
ties of  the  trachea.  The  effect  of  this  elasticity  is  de- 
monstrated in  the  living  body  by  attempts  at  suicide, 
where  the  trachea  being  cut  through,  so  great  a gap  is 
made  in  the  throat  that  it  presents  the  appearance  of  a 
part  having  been  removed.  The  deficiency  at  the  back 
part  of  the  cartilages,  is  not  filled  up  by  a continuation 
of  this  elastic  membrane.  Transverse  muscular  fibres 
are  placed,  between  the  extremities  of  the  cartilages, 
and  by  their  contractions  bring  them  towards  each 
other;  according  to  the  opinion  of  Dr.  Physick,  by 
diminishing  the  size  of  the  trachea  they  - assist  in  the 
expulsion  of  mucus.  The  trachea  is  lined  by  a continu- 
ation of  the  membrane  which  covers  the  mouth  ; it  is 
perforated  with  a great  number  of  holes  through  which 
the  mucus  passes.  Under  the  membrane  are  many 
glands,  from  the  size  of  a millet-seed  to  that  of  the 
head  of  a small  pin  ; these  glands  have  their  excretory 
tubes  terminating  in  the  orifices  just  mentioned.  These 
glands  are  also  abundant  on  the  posterior  face  of  the 
transverse  muscular  fibres. 


184 


01'  THE  TRUNK. 


At  the  lower  end  of  the  trachea,  and  about  the 
root  of  the  lungs,  is  found  the  commencement  of  a chain 
of  glands  which  follows,  for  some  distance,  the  bronchia. 
In  the  adult  they  are  black,  numerous,  and  vary  from 
the  dimension  of  a large  pin’s  head  to  that  of  a kidney 
bean.  No  excretory  ducts  are  found  belonging  to  them 
and  anatomists  generally  consider  them  as  lymphatic. 
The  bronchia,  in  dividing,  still  preserve,  for  some 
length,  the  cartilaginous  structure  of  the  trachea,  but 
as  they , approach  their  terminations  the  deficiency  at 
their  back  part  ceases  and  the  cartilages  form  sections  of 
circles  which  produce,  by  the  apposition  of  several  of 
them,  complete  cylinders.  This  arrangement  holds  till 
finally  the  cartilaginous  structure  ceases,  and  only  mem- 
brane is  left.  It  is  probable,  from  the  elasticity  of  the 
lung  and  from  its  collapsing  when  the  thorax  is  opened. 
that  the  elastic  membrane,  in  whieh  the  cartilages  are 
deposited,  forms  the  essential  cellular  structure  of  this 
organ  on  which  the  blood-vessels  are  ramified. 

The  lungs  are  furnished  from  the  aorta  with  nutri- 
tious vessels  called  Bronchial  Arteries ; they  follow  the 
course  of  the  bronchia  and  communicate  freely  with  the 
pulmonary  arteries;  notwithstanding  the  latter  they 
have  their  proper  veins,  which  empty  on  the  right  side 
into  the  vena  azygos,  and  on  the  left  into  tlie  subclavian 
vein.  The  bronchial  veins  also  communicate  freely  with 
the  pulmonary  veins. 

While  studying  the  contents  of  the  thorax  it  is  of 
the  first  importance  to  attend  to  the  relative  situation  of 


VISCERA  OF  THE  THORAX. 


185 


the  parts  included  in  the  description.  One  of  the  most 
useful  and  interesting  points  is  the  space  between  the 
two  upper  ribs,  bounded  laterally  by  the  pleurae, 
anteriorly  by  the  sternum,  posteriorly  by  the  upper 
dorsal  vertebrae,  and  having  the  top  of  the  pericar- 
dium for  its  basis.  This  cavity  is  too  irregular  to  admit 
of  comparison  with  any  thing  else  without  a hazard  of 
communicating  false  ideas  of  its  shape.  The  course  of 
the  pleura,  on  each  side,  must  be  well  attended  to,  and 
in  order  to  understand  it,  the  obliquity  of  the  first  rib 
must  be  taken  into  consideration.  Considering  the 
spine  as  a vertical  column,  the  first  rib,  so  far  from  be- 
ing horizontal,  is,  in  a majority  of  subjects,  inclined 
downwards  so  much,  that  it  makes  an  angle  of  about 
forty-five  degrees  with  the  spine;  and  the  pleura,  be- 
ing reflected  from  the  internal  edge  of  the  first  rib 
from  its  head  to  its  front  part,  will,  of  course,  observe 
a similar  obliquity.  It  is  probably  this  circumstance 
which  Sabatier,  Soemmering,  and  Colies  allude  to  when 
they  speak  of  the  pleura  rising  above  the  level  of  the 
first  rib.  This  arrangement  should  influence  the  con- 
siderations arising  from  a wound  in  the  lower  part  of 
the  neck^  as  a ball  or  sword  passing  through  horizontally 
just  above  the  sternal  end  of  the  clavicle,  would  cer- 
tainly enter  the  cavity  of  the  pleura  in  a great  number 
of  persons. 

In  this  upper  section  of  the  mediastinum,  just  at  the 
upper  edge  of  the  sternum,  are  the  remains  of  the 
Thymus  Gland,  much  shrivelled,  having  a ligament- 


186 


OF  THE  TRUNK. 


ous  feel,  and  of  a light  pink  colour.  In  contact  with  the 
pleura  on  the  right  is  the  Descending  Vena  Cava.  The 
common  trunk  of  the  left  subclavian  and  internal  jugu- 
lar, (Vena  Innominata)  after  crossing,  by  an  oblique  de- 
scent, the  upper  portion  of  the  sternum,  joins  the  de- 
scending cava  about  an  inch  above  the  place  where  the 
latter  penetrates  into  the  pericardium.  Behind  this 
transverse  vein  are  the  top  of  the  arch  of  the  Aorta, 
the  origin  of  the  Arteria  Innominata,  the  left  Carotid, 
and  the  left  Subclavian  Artery.  The  oesophagus  makes  a 
vertical  descent  just  before  the  dorsal  vertebrae,  the  tra- 
chea is  placed  before  it,  and  we  see  the  arteria  innominata 
erossingthe  latter  obliquely  from  left  to  right.  The  arte- 
ria innominata  is  placed  much  more  superficially  than 
the  left  subclavian,  being  removed  from  the  upper  end  of 
the  sternum  only  the  thickness  of  the  transverse  vein, 
and  is  very  accessible,  as  proved  by  Dr.  Mott's  opera- 
tion whereas  the  other,  being  the  last  branch  given  off 
from  the  curve  of  the  aorta  in  its  course  backwards,  is 
an  inch  deeper,  and  inaccessible  in  the  living  body.  The 
arteria  innominata  varies  much  in  length  before  its  di- 
vision into  subclavian  and  carotid;  I have  examples 
of  it  from  half  an  inch  to  two  inches,  but  the  general 
length  is  about  sixteen  lines. 

In  this  dissection  the  phrenic  nerve  is  seen  to  de- 
scend in  contact  with  the  internal  edge  of  the  scalenus 
anticus  muscle,  and  passing  between  the  subcla\Tan 

* Eclectic  Repertor3%  Vol.  9,  p.  1- 


VISCERA  OF  THE  THORAX. 


187 


artery  and  vein  to  proceed  vertically  in  contact  with 
the  pleura  at  first?  and  afterwards  between  it  and  the 
pericardium  to  the  diaphragm.  The  par  vagum  is  on 
the  inner  or  mesial  side  of  the  internal  jugular  vein,  and 
gets  into  the  thorax  'between  the  subclavian  artery  and 
vein,  near  the  origin  of  the  subclavian  artery.  The  trunk 
of  it  passes  along  the  side  of  the  trachea,  and  behind 
the  root  of  the  lungs  to  the  oesophagus  and  terminates 
at  the  stomach.  On  a level  with  the  subclavian  artery, 
the  Recurrent  or  Inferior  Laryngeal  Nerve  is  sent  olf, 
which,  to  get  to  the  larynx,  winds  around  the  sub- 
clavian of  the  right,  and  the  aorta  of  the  left  side. 
About  the  root  of  the  lungs,  the  Pulmonary  Plexus  is 
detached  from  the  Par  Vagum  nerve.  The  sympa- 
thetic nerve  lies  closer  to  the  vertebra,  and  sends  off 
from  its  two  inferior  cervical  ganglions  principally, 
the  branches  which  supply  the  heart,  by  the  cardiac 
plexus.  In  the  thorax  it  continues  its  course  by  the 
heads  of  the  ribs,  and  sending  off  the  greater  and  less- 
er Splanchnic  nerves,  is  distributed  in  a manner  to  be 
described  hereafter. 

' In  making  this  dissection  it  must  be  observed  that, 
from  the  lower  part  of  the  thyroid  gland,  the  conden- 
sed membrane  called  Fascia  Profunda  Cervicalis,  which 
seems  to  afford  protection  to  the  upper  opening  in  the 
thorax,  and  is  extended  to  the  upper  edge  of  the 
sternum,  has  beneath  it,  connecting  the  vessels  and 
other  parts  together,  a loose,  vascular,  adipose,  and 
cellular  matter,  which  must  be  removed  by  dissection, 


188 


OF  THE  TRUNK. 


before  the  rest  of  the  structure  can  be  rendered  dis- 
tinct. The  plan  for  opening  the  thorax,  by  the  ster- 
num being  sawed  in  two  longitudinally  and  kept  open 
to  the  distance  of  an  inch  or  so,  is  by  far  the  most  exact 
and  satisfactory  manner  of  studying  these  parts. 

This  stage  of  the  dissection  having  been  accomplish- 
ed, the  sternum  must  be  removed,  and  by  turning 
up  the  lungs,  we  see  the  parts  contained  in  the  poste- 
rior mediastinum  and  what  is  meant  by  it.  To  the 
left  is  the  aorta,  which  gradually  gets  to  the  front 
of  the  dorsal  vertebrae  in  the  lower  part  of  the  thorax, 
as  it  penetrates  the  erura  of  the  diaphragm.  The 
(Esophagus  is  in  the  middle  above,  but  in  getting 
to  its  own  opening  in  the  diaphragm  it  crosses  the  aorta 
very  obliquely  and  is  then  to  the  left  of  the  lower  dor- 
sal vertebrae.  The  Vena  Azygos,  made  up  of  the 
six  lower  intercostal  veins  on  the  left  side  and  the  ten 
lower  of  the  right,  occupies  the  right  side  of  the  me- 
diastinum and  forms  an  arch  at  its  termination  where 
it  joins  the  descending  cava,  over  the  root  of  the 
- right  lung.  The  Thoracic  duct  enters  the  thorax  be- 
tween the  crura  of  the  diaphragm,  and  passes  nearly 
in  the  middle  line  between  the  aorta  and  the  vena 
azygos,  till  it  reaches  the  third  dorsal  vertebra;  it 
then  inclines  to  the  left  side,  and  rising  into  the  root 
of  the  neck,  forms  an  arch  which  terminates  in  the  angle 
produced  by  the  junction  of  the  left  internal  jugular 
and  subclavian  vein.  The  Par  Vagum  is  strictly  within 
the  limits  of  the  posterior  mediastinum,  the  Sympathe 
tic  is  not. 


PART  II. 

CHAPTER  II. 

Of  the  Mdomen. 

Before  the  commencement  of  the  dissection  of  the 
Abdomen,  it  is  useful  to  acquire  a knowledge  of  its  re- 
gions, the  boundaries  of  which  are  thus  established  by 
imaginary  planes  passing  through  the  subject.  Draw 
a line  from  the  superior  part  of  one  Ilium  as  it  appears 
through  the  skin,  to  the  superior  part  of  the  other; 
strike  a perpendicular  then  from  the  anterior  inferior 
spinous  process  of  the  Ilium  on  each  side  through  the  car- 
tilages of  the  ribs  above;  then  draw  a fourth  line  parallel 
with  the  first  through  the  points  where  the  latter  touch 
the  cartilages  of  the  ribs.  These  four  lines,  two  verti- 
cal and  two  horizontal,  which  represent  as  many  planes, 
form  with  the  periphery  of  the  abdomen  nine  regions. 
The  one,  above,  on  the  right,  is  the  right  Hypochond- 
riac, that  in  the  middle  the  Epigastric,  and  that  to  the 
left,  the  left  Hypochondriac.  The  region  which  has 
the  navel  in  its  centre  is  the  Umbilical,  and  on  its  sides 
are  the  right  and  the  left  Lumbar  Regions.  Below 
the  umbilical  is  the  Hypogastric  Region,  and  on  the 
wings  of  the  latter  are  the  right  and  the  left  Iliac 
Regions. 


190 


OF  THE  TRUNK. 


So^ie  anatomists  call  the  pit  around  the  ensiforni 
cartilage  the  Scrobiculus  Cordis,  and  a small  space  just 
behind,  and  elevating  itself  about  an  inch  above  the 
pubis,  the  Regio  Pubis.  The  boundaries  of  the  latter 
are  rather  undefined,  but  the  terms  are  in  use. 


Section  I. 

Of  the  Muscles  of  the  Abdomen. 

To  begin  the  dissection  of  the  muscles  of  the  abdo- 
men, a straight  cut  must  be  made  through  the  skin 
- from  the  end  of  the  second  bone  of  the  sternum  to  the 
symphysis  pubis;  another  is  to  cross  this  at  its  com- 
mencement above,  extending  obliquely  towards  the  arm- 
pit,  till  it  reaches  the  side  of  the  chest.  The  second 
terminates  and  a third  commences  there,  having  a 
sweep  backwards,  parallel  in  its  direction  with  the 
margin  of  the  cartilages  of  the  ribs  and  equidistant  from 
it.  The  third  cut  by  being  extended  to  the  spine 
affords  an  opportunity  of  opening  the  integuments  still 
further  by  a vertical  cut  over  the  spinous  processes 
down  to  the  small  end  of  the  sacrum.  This  manner  of 
opening  the  integuments  of  the  side  of  the  belly,  de- 
scribes in  a great  measure  the  outline  of  the  external 


MUSCLES  OF  THE  ABDOMEN. 


191 


oblique  muscle,  makes  it  thoroughly  accessible  in  the 
progress  of  the  dissection,  and  enables  one  to  see  and  to 
display  every  part  of  it.  One  of  the  greatest  obstacles  ' 
(simple  as  the  circumstance  may  appear,)  to  understand- 
ing the  broad  muscles  of  the  abdomen  well,  is  the  im- 
perfect manner  in  which  the  integuments  are  opened 
by  dissectors,  and  there  is  no  dissection  more  often 
spoiled,  than  the  one  in  which  we  are  now  engaged, 
owing  to  the  want  of  a plan  (founded  on  some  previous 
knowledge  of  the  parts,)  for  commencing  operations. 
Having  thus  marked  olf  the  section  of  the  subject  on 
which  to  work,  begin  by  dissecting  at  the  upper  part, 
to  turn  the  flap  downwards.  But  few  strokes  of  the 
knife  will  be  made,  before  the  upper  fibres  of  the  exter- 
nal oblique  muscle  will  be  exposed.  The  flap  is  now 
to  be  entirely  dissected  off  as  far  down  as  the  hip  and 
thigh,  exposing,  by  such  means,  the  superior  margin  of 
the  pelvis  from  the  spine  to  the  symphysis  pubis.  The 
beginner  must  cut  very  slowly,  seeing  that  he  detaches 
fully  the  cellular  membrane  from  the  muscular  fibre, 
by  cutting  in  the  same  direction  with  the  latter ; he  will 
by  such  means  leave  it  clean  and  brilliant,  and  the  tran- 
sition from  it  to  the  broad  tendon  connected  with  it,  will 
be  comparatively  easy. 

In  this  dissection,  as  indeed  in  all  others  of  the  mus- 
cles I cannot  attach  too  much  importance  to  cutting 
in  the  course  of  the  fibres ; it  is  absolutely  essential  to 
the  beauty  of  the  display,  and  indispensable  to  a per- 
son desirous  of  success  in  practical  anatomy.  A dissec- 


192 


OF  THE  TRUNK. 


tion  done  in  any  other  manner  is  unfit  for  study  from 
its  obscurity,  and  offensive  to  inspect  from  its  rough- 
ness.  The  sum  of  directions  to  make  a good  dissector 
of  muscles,  is  to  cut  in  the  direction  of  the  fibres,  close 
to  them,  and  to  keep  the  cellular  membrane  tense. 

There  are  five  pairs  of  muscles  to  the  abdomen,  three 
broad  and  two  narrow. 

1.  Musculus  Obliquus  Externus,  arises  from  the 
eight  inferior  ribs  by  muscular  and  tendinous  digitations 
attached  near  their  anterior  extremities.  The  fii’st 
head  is  covered  by  a slip  from  the  pectoralis  major,  the 
five  upper  heads  are  interlocked  with  the  serratus 
major  anticus,  and  the  three  inferior  with  the  latissimus 
dorsi.  The  fibres  pass  obliquely  downwards,  and  ter- 
minate in  a broad  thin  tendon.  This  tendon  extends 
over  the  whole  front  of  the  abdomen  from  the  lower 
end  of  the  second  bone  of  the  sternum  to  the  symphy- 
sis of  the  pubis. 

It  is  inserted  into  the  whole  length  of  the  linea  alba, 
and  into  the  anterior  half  or  two -thirds  of  crista  of  the 
Ilium,  by  muscular  fibres  posteriorly,  and  tendinous 
anteriorly.  And  from  the  anterior  superior  spinous 
process,  the  tendon  extends  to  the  body  of  the  pubes, 
forming  thereby  the  ligament  of  Poupart. 

In  the  middle  line  of  the  body,  the  tendons  of  the 
three  broad  muscles  on  each  side  of  the  abdomen  unite 
to  form  the  Linea  Alba,  which  extends  from  the  ster 


MUSCLES  OF  THE  ABDOMEN. 


193 


iium  to  the  pubes.  From  two  to  three  inches  in  the 
adult  on  each  side  of  the  linea  alba,  but  more  distant  from 
it  above  than  bdow,  is  another  line  formed  by  the  same 
tendons,  which  is  the  Linea  Semilunaris.  The  navel, 
which  originally  was  a hole  for  the  passage  of  the  um- 
bilical vessels,  and  in  the  adult,  is  commonly  de- 
pressed into  a pit,  now  appears  in  the  linea  alba  as  a 
protuberance  composed  of  condensed  cellular  mem- 
brane. Just  at  the  navel  there  appears  a line  crossing 
the  linea  alba,  and  extending  from  one  linea  semiluna- 
ris to  the  other.  At  the  lower  end  of  the  Cartilage 
Ensiformis,  there  is  another,  and  half-way  betvyeen  this 
and  the  navel,  a third.  About  half-way  between  the 
navel  and  the  pubes  is  a fourth,  but  it  is  generally 
imperfect.  These  are  the  Linesa  Transversse,  and 
they  are  formed  by  tendinous  matter  in  the  substance 
of  the  recti  muscles,  connecting  them  to  their  tendin- 
ous sheath  in  front. 

The  most  interesting  insertion  of  the  tendon  of  the 
external  oblique  is,  the  part  constituting  PouparCs 
Ligament.  The  latter,  as  it  approaches  the  pubes 
from  the  Ilium,  splits  so  as  to  leave  a hole  for  the  pas- 
sage of  the  Spermatic  Chord  in  the  male,  and  of  the 
Round  Ligament  of  the  Uterus  in  the  female.  This 
opening  obtains  the  name  of  Abdominal  Ring.  Thq 
tendon  forming  its  upper  boundary,  is  inserted  into  the 
symphysis  pubis,  and  into  the  pubes  of  the  opposite 
side,  by  fibres  which  are  interwoven  with  and  decus- 
sate those  of  its  fellow.  The  tendon  forming  the  lower 

B b 


194 


OF  THE  TRUNK. 


margin  of  the  ring,  is  inserted  into  the  spine  of  the 
pubes,  and  into  its  crest  for  an  inch.  The  portion 
inserted  into  the  crest  of  the  pubes,  is  Gimbernat's 
ligament,  which,  it  will  be  readily  undei'stood,  means 
only  a part  of  Poupart’s. 

The  ring  in  the  External  Oblique  is  rather  triangu- 
lar than  round;  its  base  is  formed  by  the  body  of  the 
pubes,  and  its  point  is  at  the  place  where  the  tendon 
separates.  The  latter  is  kept  from  parting  still  further, 
by  a fasciculus  of  tendinous  fibres  which  runs  across  it. 
The  sides  of  this  opening  are  called  its  Columns,  and 
from  their  situation,  internal  and  external,  or  upper 
and  lower  Columns. 

There  are  several  small  round  holes  in  the  tendon  of 
this  muscle,  which  afford  passage  to  nerves  and  to  veins. 
When,  by  the  cleanness  of  the  dissection,  the  tendon 
•has  its  characteristic  gloss  and  polish,  they  are  very 
distinct. 

Use.  This  muscle  compresses  the  viscera  of  the  ab- 
domen, and  brings  the  pelvis  and  thorax  towards  each 
other. 

The  External  Oblique  is  now  to  be  turned  over  to 
the  other  side,  by  dissecting  up  its  origin  from  the  ribs, 
and  its  insertion  into  the  crista  of  the  Ilium.  This  pro- 
cess will  enable  the  student  to  gain  a more  satisfactory 
view  of  its  insertion  into  the  spine  and  crista  of  the 
pubes. 


2.  The  Obliquus  Internus  lies  beneath  the  last. 


MUSCLES  OF  THE  ABDOMEN. 


195 


and  its  fibres  pass  in  a contrary  direction  to  the  fibres 
of  the  other.  It  arises  tendinous^  by  the  fascia  lumbo- 
rnm,  from  the  three  inferior  spinous  processes  of  the 
loins  and  from  all  those  of  the  sacrum,  tendinous  and 
fleshy,  from  the  whole  length  of  the  crista  of  the  Ilium, 
and  fleshy  from  the  upper  half  of  Poupart’s  ligament. 
Though  the  fibres  of  this  muscle,  in  general,  decussate 
the  fibres  of  the  external  oblique,  all  of  them  do  not,, 
for  the  lower  are  brought  gradually  to  pursue  the  same 
direction  towards  the  symphysis  of  the  pubes. 

Near  the  Linea  Semilunaris,  the  muscular  fibres 
cease,  and  the  tendon  begins. 

It  is  inserted  into  the  cartilaginous  margin,  formed  by 
the  six  inferior  ribs ; by  tendon  resembling  condens- 
ed cellular  membrane,  into  the  cartilages  of  the  seventh, 
eighth,  and  ninth  ribs,  and  by  flesh  into  the  tenth, 
eleventh,  and  twelfth.  It  is  inserted  also  into  the  side 
of  the  ensiform  cartilage,  its  whole  length,  and  into  the 
linea  alba,  from  the  sternum  to  the  pubes. 

The  tendon  of  this  muscle  divides  into  two  laminae, 
in  a manner  which  will  be  better  explained  presently, 
after  the  rectus  and  pyramidalis  muscles  have  been  dis- 
sected and  turned  down. 

Its  use  is  the  same  as  that  of  the  External  Oblique. 

The  Internal  Oblique  is  now  to  be  dissected  up  from 
its  attachments  to  the  ribs,  vertebrae,  ilium,  and  exter- 
nal half  of  Poupart’s  ligament;  by  beginning  near  the 
spine  of  the  ilium,  where  it  is  separated  more  distinctly 


196  OF  THE  TRUNK.' 

from  the  muscle  below,  by  an  artery,  a vein,  and  cel- 
lular substance. 

3.  The  Transversalis  Abdominis,  arises  by  the 
Fascia  Lumborum,  from  the  transverse  processes  of  the 
last  dorsal,  of  the  four  upper  lumbar  vertebrie,  and 
from  the  back  part  of  the  spine  of  the  ilium.  It  also 
.arises  fleshy  from  the  anterior  two-thirds  of  the  spine 
of  the  ilium,  and  from  the  exterior  half  of  Poupart’s 
ligament;  tendinous  and  fleshy  alternately,  from  the  in- 
ferior margin  of  the  thorax  formed  by  the  cartilages 
of  the  six  or  seven  inferior  ribs,  at  their  inner  sur- 
faces, where  they  are  concerned  in  the  origin  of  the 
diaphragm. 

The  fleshy  part  of  this  muscle  occupies  about  one- 
thiini  of  its  extent.  It  is  inserted,  into  the  side  of  the 
ensiform  cartilage,  filling  up  the  vacancy  between  it 
and  the  cartilages  of  the  sixth  and  seventh  ribs,  and  into 
the  linea  alba,  from  the  extremity  of  the  sternum  to 
the  pubes. 

Use,  to  compress  the  contents  of  the  abdomen. 

4.  The  Rectus  Abdominis  muscle  is  seen  beneatli 
the  tendons  of  the  other  muscles  on  each  side  of  the 
linea  alba.  A longitudinal  cut,  its  whole  length,  is  to 
be  made  on  its  imier  edge  through  tliese  tendons,  and 
they  turned  over  towards  the  linea  semilunaris.  Its 
origin  will  then  be  seen  as  a flat  tendon  of  an  inch  oi 
more  in  breadth  from  the  symphysis  pubis  and  the 


MUSCLES  OF  THE  ABDOMEN. 


197 


upper  posterior  part  of  the  body  of  the  pubes.  The 
muscle  increases  gradually  to  the  breadth  of  three 
or  four  inches  in  its  ascent.  The  tendinous  intersec- 
tions, confining  it  to  the  tendinous  sheath  in  front,  are 
established  at  the  places  mentioned  as  lineee  transversae, 
but,  for  the  most  part,  they  do  not  extend  through  the 
muscle. 

Inserted  fleshy,  into  the  cartilagoj  ensiformis  and 
into  the  cartilages  of  the  fifth,  sixth  and  seventh 
ribs. 

It  draws  the  thorax  towards  the  abdomen. 

5.  The  Pyramidalis  is  at  the  lower  front  part  of 
the  rectus.  It  arises  somewhat  thick,  tendinous,  and 
fleshy  from  the  upper  part  of  the  pubes,  from  near  its 
spine  to  the  symphysis,  between  the  rectus  behind  and 
the  insertion  of  the  external  oblique  before.  It  is  fix- 
ed in  a sheath  formed  by  the  separation  of  the  tendons 
of  the  broad  muscles.  It  tapers  to  a point  above, 
and  is 

Inserted  into  the  linea  alba  and  internal  edge  of 
the  rectus,  half-way  between  the  umbilicus  and  the 
pubis. 

It  strengthens  the  lower  part  of  the  abdomen.* 

The  Rectus  and  the  Pyramidalis  muscles  are  now  to 
be  detached  from  their  origins  and  turned  aside.  By 
doing  so  we  become  sensible  of  an  arrangement  of  the 


* Tills  muscle  is  often  wanting. 


4 


198  OF  THE  TRUNK. 

tendons  of  the  broad  muscles  always  difficult  to  describe 
intelligibly,  and  generally  imperfectly  understood.  It 
is  this:  at  the  linea  semilunaris  the  tendon  of  the  in- 
ternal oblique  and  transversalis  unite  intimately,  and 
just  beyond  this  junction  two  laminse  are  formed,  which 
enclose  the  rectus  muscle.  The  anterior  lamina  is  one- 
half  of  the  tendon  of  the  internal  oblique,  which,  after 
passing  half  an  inch  or  an  inch,  is  joined  to  the  ten- 
don of  the  external  oblique,  goes  in  front  of  the  rec- 
tus muscle?  and  covers  it  from  origin  to  insertion.  The 
posterior  lamina,  made'  by  the  posterior  half  of  the  ten- 
don of  the  internal  oblique,  is  united  already  at  the 
linea  semilunaris  to  the  tendon  of  transverealis ; in  this 
manner  they  pass  behind  the  rectus  muscle  from  the 
cartilago  ensiformis  to  a line  half-way  between  the  um- 
bilicus and  the  pubes.  From  this  line  downwards,  all 
the  tendons  go  in  front  of  the  rectus  muscle.  The  ob- 
liquus  externus  tendon  may,  however,  be  dissected 
from  the  common  tendon  of  the  others,  without  much 
difficulty,  almost  to  the  linea  alba. 

The  term  insertion  is  very  inadequate  to  express  the 
manner  in  which  the  tendons  of  these  broad  muscles  all 
terminate  in  the  linea  alba  from  the  thorax  to  the  pel- 
vis, but  the  inspection  of  the  part  will  qualify  the  term 
so  as  to  prevent  mistakes. 

The  Cremaster  muscle  is  commonly  attributed  ex 
clusivelyto  the  internal  oblique,  as  it  is  said  to  beade 


MUSCLES  OF  THE  ABDOMEN, 


199 


tachmeiit  of  fibres  from  it.  The  dissection  is  now  in  a 
stage  to  exhibit  what  is  really  the  fact  in  regard  to  this 
muscle^ — that  it  is  also  formed  by  fibres  from  the  lower 
edge  of  the  transversalis  muscle.  The  history  of  its 
formation  is  as  follows  : in  the  descent  of  the  testicle, 
the  testicle  has  to  pass  beneath  that  edge  of  the  trans- 
versalis and  of  the  internal  oblique  which  is  extended 
from  the  upper  part  of  Poupart’s  ligament  to  the  spine 
of  the  pubes.  As  it  descends  it  comes  in  contact  with 
a fasciculus  of  these  fibres  and  takes  it  along.  This  con- 
stitutes the  Cremaster  muscle,  which,  in  adult  life  and 
in  a strong  muscular  subject,  is  seen  descending  on  the 
outside  of  the  spermatic  chord,  and  spreading  over 
the  anterior  part  of  the  tunica  vaginalis  in  arches  with 
their  convexities  downwards,  then  rising  on  the  in- 
ner side  of  the  chord  and  inserted  into  the  spine  of  the 
pubes.* 

It  draws  up  the  testicle. 

As  one  becomes  acquainted  with  the  dissection  of 
this  part  by  operating  on  a number  of  subjects,  he  will 
be  sensible  that  there  are  differences  in  individuals 
which  render  the  established  descriptions  occasionally 
unsuitable.  One  of  the  most  usual  is  the  deficiency  of 

* Mr.  J.  Cloquet  of  Paris,  has  given  this  explanation  of  the 
formation  of  the  cremaster  and  it  sometimes  is  manifest  in  tlie 
adult ; it  is,  howevei',  not  in  accord  with  Mr.  Hunter’s  account 
of  it,  neither  does  it  correspond  with  what  I have  witnessed  in 
the  male  buffalo.  Mr.  Hunter  has  seen  it  running  up  to  the  tes- 
tis, while  the  latter  was  still  in  the  loins. 


200 


OF  THE  TRUNK. 


the  transverse  muscle  in  that  part,  the  origin  of  which 
is  usually  attributed  to  the  upper  half  of  Poupart's 
ligament.  In  this  case  the  internal  oblique  has  in- 
creased thickness,  and,  of  course,  the  cremaster  will 
be  exclusively  derived  from  it.  In  other  instances  the 
two  muscles  are  so  much  blended  that  they  cannot  be 
satisfactorily  separated  from  each  other. 

The  Transversalis,,  and  the  Internal  Oblique  per- 
form so  important  a part  in  the  doctrines  of  Hernia, 
that  one  desirous  of  understandig  them  wxll,  should  at 
this  time,  pay  attention  again  to  the  mode  of  their  in- 
sertion into  the  pubes.  It  will  thus  be  seen  that  they  form 
below,  a common  tendon,  w hich  is  inserted,  for  an  inch, 
into  the  crista  of  the  pubes  behind  GimbernaPs  liga- 
ment, into  its  spine,  and  into  that  part  of  its  body 
which  is  behind  the  annulus  abdominalis;  and  that  just 
within  and  above  their  insertion  the  same  common  ten- 
don splits  into  two  laminae,  one  going  before,  the  other 
behind  the  pyramidalis  muscle,  thus  forming  a sheath 
for  it. 

In  examining  the  origins  of  the  Recti  muscles  from 
behind,  the  peritoneum  being  stripped  off,  it  will  be 
seen  that  a protusion  of  intestine  between  them  is  pre- 
vented by  the  internal  edge  of  the  one  tendon  over- 
lapping the  internal  edge  of  the  other,  and  by  a trian- 
gular ligament  called,  by  Mr.  Breschet  its  discoverer, 
the  Superior  Pubic  Ligament. 


INGUINAL  HERNIA. 


201 


Section  II. 

On  the  parts  concerned  in  Inguinal  Hernia, 

It  is  better  for  the  student  to  postpone  the  subject 
of  Hernia  until  he  has  become  acquainted  with  the  ab- 
dominal muscles  and  the  contents  of  the  abdomen. 
When  he  has  paid  due  attention  to  what  is  remarked 
concerning  them,  the  rest  of  the  investigation  will  be 
comparatively  easy. 

Make  an  incision  through  the  skin  and  fat,  from  the 
Umbilicus  to  the  dorsum  of  the  Penis,  and  for  three 
or  four  inches  along  the  inner  margin  of  the  thigh ; 
commence  another  at  right  angles  with  the  beginning 
of  this,  and  continue  it  from  the  umbilicus  in  a straight 
line  towards  either  flank ; make  a third  incision  parallel 
with  the  first,  beginning  an  inch  behind  the  anterior 
superior  spinous  process  of  the  ilium,  and  terminating 
in  the  second  incision.  The  flap  of  skin  thus  marked 
out,  must  be  turned  down  over  the  thigh  by  a care- 
ful dissection,  which  will  bring  into  view  the  fascia 
superficialis  abdominis. 

The  Fascia  Superficialis  consists  of  condensed 
cellular  membrane,  which  may  be  considered  as  taking 
its  origin  on  the  front  of  the  thigh,  and  extending  in 


202 


OF  THE  TRUNK. 


front  of  the  abdominal  muscles,  as  higli  up  as  the  thorax ; 
indeed,  if  we  are  disposed  to  trace  it  to  its  whole  ex- 
tent, there  is  no  difficulty  in  following  it  over  the  front 
of  the  thorax,  also  to  the  neck,  and  even  to  the  face. 
In  ordinary  cases  its  aponeurotic  character  is  very 
equivocal,  but  where  the  parts  about  the  groin  have  been 
pressed  upon  and  tliickened  by  the  irritation  of  hernial 
protusion  it  is  better  developed.  On  the  thigli  it  i^ 
blended  with  fat,  and  encloses  between  its  laininsB  the 
lymphatic  glands  of  the  groin,  and  the  small  vessels 
given  off  from  the  femoral  artery  immediately  below 
Poupart's  ligament.  On  the  tendon  of  the  external  ob- 
lique it  is  more  condensed;  branches  of  the  femoral  ar- 
tery are  also  seen  in  it  there ; one  longer  and  larger  than 
the  others,  the  arteria  ad  cutem  abdominis  of  Haller 
winds  over  Poupart’s  ligament  and  runs  upwards  some- 
what in  the  line  of  the  epigastric  artery,  being  distri- 
buted to  the  skin  of  the  abdomen ; the  division  of  it 
will  produce  sufficient  hemorrhage  to  require  attention. 
On  the  symphysis  pubis  and  about  the  external  ring 
the  laminsB  of  the  fascia  superficialis  are  multiplied,  and 
it  has  more  of  the  character  of  common  adipose  matter, 
as  in  all  cases  the  adeps  there,  is  abundant.  This  fascia 
is  more  loosely  connected  to  the  parts  beneath  it,  along 
the  anterior  margin  of  Poupart’s  ligament  than  else- 
where, which  disposes  the  femoral  hernia  to  observe 
that  course  in  its  increase.  From  the  pubes  it  may  be 
traced  as  a condensed  cellular  membrane  along  the 
penis  to  its  extremity,  and,  according  to  Mr.  Colies  of 


INGUINAL  HERNIA. 


203 


Dublin,  wlieii  matter  is  formed  beneath  it,  it  is  apt  to 
create  fistulous  sores  on  this  organ.  A thin  edge  of 
this  membrane  may  be  traced  for  some  distance  reflect- 
ed along  the  spermatic  cord. 

The  Fascia  Superficialis,  under  the  name  of 
Tunica  Abdominalis,  is  well  developed  in  animals  with 
a large  and  projecting  belly,  particularly  in  the  large 
ruiniuantia  and  the  solipedia.  It  has  a yellowish  tinge, 
is  very  elastic  and  strong,  and  well  calculated  to  sup- 
port the  viscera  in  them. 

In  dissecting  at  the  Abdominal  Ring,  do  not  work 
too  closely  between  the  spermatic  cord  and  the  margin 
of  the  ring ; by  which  precaution  we  avoid  cutting  a 
process  of  the  fascia  superficialis  that  unites  the  two. 
This  process  arises  from  the  margin  of  the  ring  all 
around;  it  passes  immediately  to  the  spermatic  cord,  and 
is  lost  insensibly  on  the  exterior  surface  of  the  cremaster 
muscle.  A quantity  of  loose  cellular  substance,  inter- 
mixed with  fat,  is  placed  between  "the  constituent  parts 
of  the  cord  and  the  cremaster  muscle.  This  eellular 
substance,  the  cremaster  muscle,  and  the  fascia,  form,  in 
scrotal  ruptures,  a thick  lamina  over  the  hernial  sac, 
called  Tunica  Vaginalis  Communis. 

Next  make  an  incision  through  the  tendon  of  the  ex- 
ternal oblique,  commencing  at  the  Linea  Semilunaris, 
a quarter  of  an  inch  above  the  upper  margin  of  the 


204 


OF  THE  TRUNK. 


ring,  and  ending  a quarter  of  an  inch  above  the  anterior 
superior  spinous  process  of  the  Ilium.  This  incision 
should  be  regularly  curved,  its  convexity  being  down- 
wards, and  almost  touching  the  middle  of  Poupart’s 
ligament.  The  tendon  of  the  external  oblique,  border- 
ing on  the  incision,  should  be  then  turned  upwards 
and  downwards,  by  which  a good  view  is  given  of  the 
inferior  part  of  the  internal  oblique  muscle  where  it 
arises  from  the  iliac  or  upper  half  of  Poupart’s  liga- 
ment, and  is  inserted  into  the  crista  of  the  pubes  just 
behind  the  external  abdominal  ring.  The  origin  of 
the  cremaster  muscle  is  well  seen,  and  the  constituent 
parts  of  the  cord,  as  they  are  about  to  enter  into  the' 
external  ring. 

Separate  the  inferior  margin  of  the  internal  oblique 
from  Poupart’s  ligament,  and  turn  it  upwards,  begin- 
ning near  the  anterior  spine  of  the  ilium,  where  the 
distinction  between  the  internal  oblique  and  the  trans- 
versalis  is  better  marked.  The  lower  part  of  the 
transversalis  is  thus  exhibited  placed  behind  the  inter- 
nal oblique,  and  having  the  same  origin  from  Poupart’s 
ligament  and  insertion  into  the  Crista  of  the  Pubes. 
The  raising  of  the  internal  oblique  brings  into  view 
more  of  the  spermatic  cord  near  the  external  ring. 

The  Transversalis  Muscle  is  then  to  be  detached 
from  Poupart’s  ligament,  and  raised  up.  This  gives  a 
complete  view  of  the  spermatic  cord,  consisting  here, 


INGUINAL  HERNIA. 


205 


of  its  vessels,  nerves,  and  excretory  duct,  united  by 
cellular  membrane.  The  upper  part  of  the  visible 
portion  of  the  cord  is  about  half-way  between  the 
anterior  spine  of  the  ilium  and  the  symphysis  of  the 
pubes,  and  penetrates  the  fascia  transversalis.  The 
fascia  transversalis  is  placed  immediately  behind  the- 
transversus  muscle,  between  it  and  the  peritoneum. 
The  opening  of  the  fascia  transversalis,  which  permits 
the  cord  to  pass,  is  called  the  Internal  Abdominal 
Ring,  in  order  to  distinguish  it  from  the  opening  in 
the  tendon  of  the  external  oblique,  called  now  the  Ex- 
ternal Ring.  The  internal  ring  is  rather  nearer  to  the 
symphysis  pubis  than  to  the  spine  of  the  ilium.  It  will 
now  be  understood  that  the  space  between  the  internal 
ring  and  the  external  ring,  is  about  eighteen  lines  in 
the  adult,  and  that  it  is  very  properly  called  the  Abdo- 
minal Canal,  as  giving  passage  to  the  spermatic  cord. 
The  anterior  side  of  the  canal  is  formed  by  the  tendon 
of  the  external  oblique;  the  inferior  part  in  the  erect 
posture,  is  formed  by  Gimbernat’s  ligament;  the  pos- 
terior parietes  are  formed  by  the  fascia  transversalis, 
and  above,  this  canal  is  overhung  by  the  internal  oblique 
and  transversalis  muscles.  It  should  be  observed  that 
the  spermatic  cord,  after  penetrating  the  fascia  trans- 
versalis, does  not  cross,  directly,  the  inferior  edge  of 
the  internal  oblique  and  transversalis  at  right  angles ; 
but  it  crosses  them  very  obliquely,  its  inclination 
being  towards  the  pubes,  so  that  the  spermatic  cord 
can  only  be  considered  as  disengaged  from  the  inferior 


206 


OF  THE  TRUNK. 


edge  of  these  muscles,  about  the  middle  of  the  abdo  • 
minal  canal. 

The  opening  in  the  Fascia  Transverealis  is  not  abrupt 
and  well  defined;  but  the  fascia,  where  it  transmits  the 
spermatic  cord,  is  reflected  by  a thin  process  to  the 
cord,  and  insensibly  terminates  on  its  cellular  substance. 
At  the  posterior  or  ventral  face  of  the  External  Ring, 
the  fascia  transvei’salis  is  not  in  contact  with  the  cord, 
but  that  part  of  the  tendon  of  the  internal  oblique  and 
transversalis  which  is  inserted  into  the  crista  of  the 
pubes,  and  forms  a sheath  for  the  pyramidalis  muscle, 
is  placed  between  them,  and  secures  this  opening. 

The  incisions  which  were  originally  made  only 
through  the  skin  of  the  abdomen  are  now  to  be  carri- 
■ ed  through  the  parietes  of  the  same  into  its  cavity, 
and  the  flap  thus  constituted,  to  be  turned  down  in  order 
to  get  a view  of  its  posterior  or  ventral  face.  This 
surface  covered  by  peritoneum  is  divided  in  the  iliac  re- 
gion near  the  middle  of  Poupart’s  ligament  into  two 
superficial  fossse  by  a narrow  falciform  process  of  the 
peritoneum.  The  pi’ocess  arises  froiii  the  side  of  the 
bladder  and  extends  upwards  and  inwards  towards  the 
umbilicus,  stopping  about  two  inches  short  of  the  um- 
bilicus. It  is  broader  below  than  it  is  above,  and 
its  loose  edge  is  turned  towards  the  abdomen.  By 
stripping  down  the  peritoneum  we  shall  see  that  this 
falciform  process  is^ simply  a duplicature  of  it,  occasion- 


INGUINAL  HERNIA. 


207 


ed  by  a fibrous  cord,  the  umbilical  ligament  of  the  blad- 
der, which  once  was  the  umbilical  artery  of  the  foetus. 
The  cord  passes  near  the  pubic  margin  of  the  internal 
abdominal  ring.  Replacing  the  peritoneum  we  be- 
come convinced  that  the  bottom  of  the  superficial  fossa 
on  the  outer  or  iliac  side  of  the  falciform  process,  cor- 
responds with  the,  internal  abdominal  ring,  and  fre- 
quently a little  pouch  of  peritoneum  enters  the  lat- 
ter. The  fossa  on  the  inner  or  pubic  side  of  the  falci- 
form process  is  just  behind  the  external  ring,  but  sepa- 
rated from  it  by  the  fascia  transversalis,  and  the  ten- 
dons of  the  lower  parts  of  the  internal  oblique,  and  the 
transversalis  muscles  where  they  are  inserted  into  the 
pubes,  and  form  the  sheath  of  the  pyramidalis.  The 
two  fossae  indicate  the  points  where  inguinal  herniac 
commence,  the  proper  inguinal  protusion  beginning  in 
the  external  fossa,  and  the  ventro-inguinal  in  the  inter- 
nal fossa.  We  should  here  notice  the  looseness  of  the 
attachment  of  the  peritoneum  by  cellular  substance  to 
the  parietes  of  the  abdomen,  and  consequently  the  little 
resistance  which  it,  unsupported,  can  afford  against  in- 
testinal protusion. 

The  view  of  the  Fascia  Transversalis  from  behind 
is  extremely  satisfactory.  For  a proper  knowledge  of 
this  membrane,  the  profession  is  indebted  to  the  labours 
of  Sir  Astley  Cooper,  and  much  of  the  zeal  with  which 
the  anatomy  of  hernia  has  been  investigated,  in  latter 
years  is  attributable  to  him.  Tlie  fascia  transversalis 


208 


OP  THE  TRUNK. 


is  a thin  tendinous  membrane  most  generally,  occasion- 
ally it  resembles  more,  condensed  cellular  membrane. 
It  arises  from  the  internal  or  abdominal  edge  of  Pou- 
part’s  ligament,  and  from  the  crista  of  the  pubes  just 
behind  the  insertion  of  the  tendon  of  the  internal  ob- 
lique and  transversalis  muscles,  and  is  extended  up- 
wards on  the  posterior  face  of  the  transversalis  muscle  to 
the  thorax.  At  its  origin  it  is  attached  to  the  inferior 
edge  of  the  transversalis  and  internal  oblique,  particu- 
larly the  part  of  the  edge  between  the  internal  ring  and 
the  pubes.  It  is  also  attached  to  the  exterior  margin 
of  the  rectus  abdominis.  The  internal  ring  or  opening 
in  this  fascia  marks  it  out  in  some  measure  as  consisting 
of  two  portions,  that  on  the  iliae  side  of  the  ring  is  not  so 
thick  as  the  other,  or  the  one  on  its  pubic  side,  and 
both  portions  are  much  more  tendinous  near  the  crural 
arch  than  they  are  higher  up.^ 

Removing  the  peritoneum  from  the  iliacus  internus 
muscle,  we  see  the  spermatic  vessels  descending  from 
the  loins  to  the  internal  ring,  where  they  are  joined 
by  the  vas  deferens  coming  from  the  pelvis.  As  they 

* Were  it  not  for  the  important  influence  of  the  fascia  super- 
ficlalis  and  the  fascia  transversalis  upon  hernia,  and  the  con- 
sequent necessity  of  a minute  knowledge  of  them,  the  descrip- 
tion might  be  much  curtailed  in  considering  them  in  their  proper 
light,  to  wit:  as  the  sheaths  of  muscles;  for  it  is  now  sufiiciently 
apparent  that  the  first  is  contiguous  to  the  external  oblique  and 
the  second  to  the  transverse  muscle. 


INGUINAL  HERNIA. 


209 


engage  under  the  edge  of  the  internal  oblique  muscle, 
after  penetrating  the  ring,  the  cremaster  muscle  is 
detached  to  spread  itself  over  them.  The  spermatic 
cord,  thus  constructed,  passes  through  the  abdominal 
canal  in  the  manner  mentioned,  obliquely  downwards 
and  inwards;  emerging  from  the  external  ring  it  des- 
cends vertically,  lying  rather  upon  the  outer  column 
of  the  ring  than  upon  its  base. 

On  the  posterior  face  of'  the  fascia  transversalis,  be- 
tween it  and  the  peritoneum,  is  the  Epigastric  Artery. 
The  epigastric  arises  from  the  external  iliac  as  the 
latter  is  about  to  go  under  the  crural  arch;  it  ascends 
inwardly  along  the  internal  margin  of  the  internal 
abdominal  ring  to  the  exterior  margin  of  the  rectus 
abdominis  muscle,  which  it  reaches  after  a course  of 
two  and  a half  or  three  inches.  The  spermatic  cord, 
in  getting  from  the  abdomen  to  the  abdominal  canal, 
therefore,  winds,  in  part,  around  the  epigastric  artery, 
in  the  first  of  its  course  being  at  the  iliac  edge  of  the 
artery  and  then  in  front  of  it.  Two  epigastric  vein§ 
attend  the  artery,  one  on  each  side,  which  end  by  a 
common  trunk  in  the  external  iliac  vein. 

From  what  has  been  said  it  will  now  be  more  fully 
understood  that  this  structure  admits  of  two  places  of 
protusion.  In  the  first,  the  intestine  protudes  the  peri- 
toneum through  the  internal  ring  and  along  the  abdo- 
minal canal  into  the  groin,  the  constituent  parts  of  the 
cord  being  below  the  sac  and  separated  by  it  from  the 

D d 


210 


OF  THE  TRUNK. 


cremaster  muscle,  which,  in  this  case,  forms  one  of  the 
envelopes  of  the  sac.  In  the  second,  from  weakness  of 
the  fascia  transversalis  and  the  pubic  insertion  of  the 
internal  oblique  and  transversalis  muscles,  a protusion 
immediately  from  behind  the  external  ring  may  occur, 
in  which  the  whole  cord,  including  the  cremaster,  is 
at  the  outer  margin  of  the  sac.  In  the  first  species,  or 
the  Inguinal  Hernia,  the  epigastric  artery  is  at  the 
pubic  side  of  the  neck  of  the  sac ; but  in  the  second, 
or  the  Ventro-Inguinal,  it  is  at  the  iliac  side. 

The  anatomical  arrangement  of  the  parts  concerned 
in  inguinal  hernia  in  the  female  is  the  same  as  in  the 
male,  except  that  the  round  ligament  of  the  uterus 
supplies  the  place  of  spermatic  cord,  and  there  is  no 
cremaster  muscle. 


Section  III. 

Of  the  parts  concerned  in  Femoral  Hernia, 

The  study  of  Femoral  Hernia  should  be  commen- 
ced with  precise  ideas ; of  the  concave  edge  of  the  os 
innominatum,  which  terminates  externally  by  the  an- 
terior superior  spinous  process  of  the  ilium,  and  inter- 
nally by  the  symphysis  pubisj— also  of  the  muscles  of 


FEMORAL  HERNIA.  211 

the  lower  extremity  which  are  connected  with  this 
edge; — and  of  the  insertion  of  the  tendon  of  the  exter- 
nal oblique. 

/ 

A muscular  subject  without  much  fat  answers  suf- 
ficiently w’ell  for  this  dissection;  the  male  black  is, 
therefore,  most  frequently  resorted  to  in  our  school.  If 
the  subject  have  suffered  somewhat  from  a previous 
infiltration  or  dropsy  of  the  cellular  membrane,  the 
facility  of  separating  the  different  layers  of  fascia  from 
each  other  is  much  increased.  Make  an  incision 
through  the  skin  from  the  umbilicus  to  the  root  of  the 
penis,  and  extend  the  lower  end  of  the  incision  around 
the  penis  along  the  internal  margin  of  the  thigh  for  six 
inches.  Commence  a second  incision  at  the  umbilicus, 
and  carry  it  out  to  the  flank  of  the  side  on  which  you 
operate.  Begin  a third  incision  through  the  skin  at 
the  termination  of  the  first  and  carry  it  to  the  outer  side 
of  the  thigh.  A flap,  consisting  simply  of  skin,  being 
thus  described,  is  to  be  carefully  raised  and  turned  out 
of  the  way.  In  raising  this  flap  of  skin  guard  against 
cutting  up  with  it  the  fascia  superficialis  abdominis, 
which  lies  immediately^beneath. 

The  Fascia  Femoris  is  beneath  the  fascia  superfi^ 
cialis;  its  general  character  and  arrangement  is  intro- 
duced into  the  account  of  the  lower  extremity,  but 
there  are  other  and  minute  circumstances  in  its  dispo- 
sition at  the  groin,  indispensable  ^ a knowledge  of 


212 


OF  THE  TRUNK. 


femoral  hernia.  When  the  fascia  superficialis  is  clear- 
ed away,  the  fascia  femoris  is  seen  to  arise  at  the 
groin  along  the  anterior  edge  of  Poupart’s  ligament, 
from  the  spine  of  the  ilium  to  within  a short  distance 
of  the  spine  of  the  pubes.  This  portion  of  it  is  thin, 
and  through  it  the  sartorius  muscle  may  be  seen.  The 
fascia  arises  also  from  the  crest  of  the  pubes,  and  along 
its  ilio  pectineal  ridge  which  is  a continuatioTi  of  the 
same ; this  latter  portion  covers  the  pectineus  muscle. 
The  one  is  called  the  sartorial,  and  the  other,  the  pec- 
tineal fascia.  The  pectineal  fascia  is  behind  the  fe- 
moral artery  and  vein,  and  the  sartorial  fascia  is  be- 
fore them. 

The  Saphena  Vein,  placed  between  the  fascia  fe- 
moris and  the  fascia  superficialis,  runs  up  along  the 
Inner  side  of  the  thigh,  and  joins  the  femoral  vein  an 
inch  and  a half  below  Poupart’s  ligament.  Raise  the 
saphena  where  it  joins  the  femoral  vein,  and  beneath 
this  junction  a rounded  semicircular  edge  of  the  fascia 
femoris  is  seen,  where  the  sartorial  fascia  becomes  con- 
tinuous with  the  pectineal.  Apply  the  end  of  a finger 
to  this  edge  and  draw  it  downwards.  Immediately  on 
its  being  made  tense,  the  sartorial  fascia  will  show  itself 
to  terminate  by  a thin  edge  in  front  of  the  femoral  vein. 
This  edge  is  concave  or  crescentic,  and  extends  from 
the  junction  of  the  sartorial  and  pectineal  fascia  to  near 
the  crista  of  the  pubes.  At  the  upper  end  of  this 
crescent;  the  sartqfial  fascia  terminates  in  a point  or 


FEMORAL  HERNIA. 


213 


angle  which  is  turned  inwards  towards  the  pubes.  The 
upper  margin  of  the  angle  is  closely  connected  with 
Gimbernat’s  ligament  near  its  edge,  and  the  point  is 
inserted  into  the  pectineal  fascia  over  the  crista  of  the 
pubes  and  for  a line  or  two  below  it,  just  at  the  internal 
margin  of  the  femoral  vein,  or  rather  about  half-way 
between  it  and  the  spine  of  the  pubes.  This  angular 
production  or  elongation  of  the  sartorial  fascia  is  called 
Key’s  or  the  Femoral  Ligaipent. 

By  introducing  a finger  under  Key’s  ligament  into 
the  abdomen,  we  find  that  the  crural  arch  or  Poupart’s 
ligament,  and  the  sartorial  fascia  exercise  a mutual 
tension  on  each  other  like  the  falx  major  and  the  ten- 
torium; by  abducting  the  limb  very  much  and  turning 
the  toe  outwards,  the  greatest  rigidity  is  given  to  both, 
but  by  making  the  limb  cross  the  other  and  turning  the 
toe  inwards,  both  are  relaxed. 

A posterior  view  must  now  be  taken  by  opening 
the  abdomen.  The  peritoneum  must  be  separated 
from  the  abdominal  muscles,  from  the  iliacus  internus 
and  psoas  magnus,  which  brings  into  view  the  fascia 
iliaca. 

The  Fascia  Iliaca  is  a tendinous  membrane  which 
lies  on  the  iliacus  internus  and  psoas  magnus  muscles, 
and  is  continued  into  the  tendon  of  the  Psoas  Parvus. 
Externally  it  is  connected  to  the  margin  of  the  crista 
of  the  ilium  ; at  the  internal  -edge  of  the  psoas  magnus 


214 


OF  THE  TRUNK. 


it  is  connected  with  the  brim  of  the  pelvis  and  sinks 
into  the  cavity  of  the  pelvis,  being  continuous  with  the 
Aponeurosis  Pelvica ; and  below,  it  is  inserted  into  the 
edge  of  the  crural  arch  from  the  anterior  superior 
spinous  process  of  the  ilium  almost  to  the  pubes.  The 
external  iliac  vessels  are  upon  this  fascia  between  it  and 
the  peritoneum;  by  raising  them  with  a knife-handle  it 
will  be  seen  that  the  fascia  iliaca  goes  over  that  part  of 
the  pubes  which  gives  origin  to  the  pectineus  muscle, 
and  that  it  is  continuous  with  the  pectineal  fascia.  If  the 
student  should  have  a preparation  in  which  every  thing 
is  removed  from  the  os  innominatum  except  the  insertion 
of  the  tendon  of  the  external  oblique,  it  will  be  of  essen- 
tial service  to  him  here  : for  by  it  will  be  seen  the  arch- 
ed form  of  the  edge  of  the  tendon  next  to  the  bone, 
from  whence  the  name  Crural  Arch ; the  vacancy 
which  exists  between  the  bone  and  the  arch ; and  the 
insertion  of  Gimbernat’s  ligament  from  the  spine  of 
the  pubes,  an  inch  or  more  along  its  crista.  He  will 
then  understand  how  this  space  is  only  partly  filled 
by  the  iliacus  internus  and  psoas  magnus,  and  that  if 
the  fascia  iliaca  had  not  an  attachment  to  the  crural 
arch  so  as  to  keep  it  down  towards  these  muscles,  her- 
nial protusions  would  be  constantly  occurring. 

The  iliac  vessels  pass  beneath  the  crural  arch  on  the 
inner  margin  of  the  psoas  magnus  muscle,  the  vein  be- 
ing nearest  the  pubes  and  the  artery  at  the  outer  side 
of  the  vein.  Close  inspection  will  satisfy  us  that  the 


femoral  hernia. 


215 


fascia  iliaca  is  inserted  into  the  crural  arch  as  far  as 
the  vein,  and  may  indeed  be  traced  to  the  crista  of 
the  pubes,  and  that  it  is  so  connected  with  the  vessels 
that  no  opening  for  hernia  exists  between  them,  or 
indeed  in  all  the  space  from  the  internal  margin  of 
the  vein  to  the  spine  of  the  ilium.  But  at  the  inner 
side  of  the  vein  between  it  and  Gimbernat’s  ligament 
an  opening  appears  called  the  Crural  Ring,  and  is 
the  place  where  femoral  hernia  commences.  This 
opening  is  generally  occupied  by  a lymphatic  gland 
and  a lamina  of  condensed  but  loosely  attached  cel- 
lular substance  continuous  with  the  Aponeurosis  Pel- 
vica. 

Make  a cross  cut  of  an  inch  in  length,  through  the 
Fascia  Iliaca;  then,  by  introducing  the  finger,  ora 
knife-handle  through  this  cut,  downwards,  our  concep- 
tions of  the  attachment  of  the  fascia  iliaca  with  the  cru- 
ral arch,  and  its  continuity  with  the  fascia  pectinea,  will 
be  much  improved. 

The  femoral  vessels  are  enveloped  by  a sheath.  In 
order  to  see  this  distinctly,  separate  the  fascia  trans- 
versalis  from  the  transverse  muscle;  cut  vertically 
through  the  falciform  process  of  the  fascia  lata,  over 
the  artery,  and  continue  the  cut  also  through  Poupart's 
Ligament,  taking  care  to  injure  the  fascia  transversalis 
as  little  as  possible.  In  order  to  render  this  part  of 
the  examination  convenient,  only  a narrow  flap  of  the 


216 


OF  THE  TRUNK. 


abdominal  muscles  should  be  left  at  the  groin.  By 
turning  towards  the  symphysis  pubis  the  falciform  pro- 
cess, with  that  part  of  Poupart’s  ligament  to  which  it 
adheres,  we  shall  see  that  the  fascia  transversalis  is  not 
only  attached  to  the  edge  of  the  crural  arch,  but  that 
it  continues  to  the  thigh  in  front  of  the  femoral  vessels. 
The  fascia  iliaca,  besides  its  connexion  with  the  pecti- 
neal fascia,  gives  a layer  to  the  posterior  face  of  the 
femoral  vessels.  The  crural  sheath  is  then  formed  from 
the  fascia  transversalis'  in  front,  and  the  fascia  iliaca  be- 
hind. Mr.  Colies  has  adopted  a very  satisfactory  mode 
of  describing  the  formation  of  the  crural  sheath,  which 
I think  more  expressive  than  such  as  are  most  in  use. 
The  fascia  transversalis  and  iliaca,  he  considei’s  as  a con- 
tinuous membrane,  which  maybe  compared  to  a funnel, 
from  the  manner  in  which  it  lines  the  lower  part  of  the 
abdomen.  The  inner  side  of  the  funnel  is  deficient. 
From  its  lower  part  proceeds  the  membranous  neck 
which  surrounds  the  femoral  vessels,  and  constitutes 
their  sheath.  This  sheath  is  very  separable  from  the 
fascia  lata  in  front,  and  the  pectineal  fascia  behind, 
and  may  be  traced,  easily,  to  the  entrance  of  the  sa- 
phena vein  into  the  femoral.  On  the  thigh,  just  below 
Poupart’s  ligament,  it  has  a number  of  foramina  in  it 
occasioned  by  the  passage  of  the  lymphatic  vessels  from 
the  surface  of  the  thigh. 

At  the  place  where  the  fascia  iliaca  is  united  to  the 
crural  arch,  a white  line  appears,  formed  by  their  union: 


FEMORAL  HERNIA. 


21T 


in  this  is  fixed  tlie  Arteria  Circuniflexa  Ilii,  coming 
from  the  external  iliac.  The  epigastric  artery  is  about 
half  an  inch  distant  from  the  Femoral  or  Crural  Ring, 
at  its  outer  side.  Occasionally,  the  Obturator  Artery 
comes  from  the  Epigastric,  and  winds  around  the  in- 
ternal margin  of  the  ring.  As  the  iliac  vessels  enter 
the  sheath  beneath  PouparCs  ligament,  a close  fibrous 
connexion  is  formed  from  them  to  the  sheath,  both 
anteriorly  and  posteriorly,  which  sends  a partition  be- 
tween the  artery  and  the  vein,  and  a partition  also  on 
the  inner  side  of  the  vein.  By  such  arrangement,  her- 
nial protusions,  are  prevented  at  this  spot;  the  only 
opening  for  them,  being  at  the  inner  side  of  the  vein 
between  it  and  GimbernaPs  ligament  or  at  the  Crural 
Ring,  as  stated. 

When  an  intestine  descends,  it  passes  into  the  femo- 
ral sheath  on  the  inner  side  of  the  iliac  vein,  it  follows 
the  course  of  this  vein  down  the  sheath,  till  it  comes 
to  an  aperture  made  by  one  of  the  lymphatic  vessels; 
it  then  protrudes  through  this  aperture,  and  gets  under 
the  fascia  superficialis.  Afterwards,  if  the  hernia  in- 
crease, instead  of  continuing  to  descend,  it  turns  up- 
wards and  outwards,  towards  the  anterior  spine  of  the 
ilium.  From  this,  it  is  obvious,  that  the  places  of  stric- 
ture may  be;  First,  the  opening  in  the  femoral  sheath 
for  the  lymphatic;  Secondly,  Hey’s  Ligament;  and 
Thirdly,  the  edge  of  Gimbernat’s  Ligament  which 
looks  towards  the  iliac  vein.  Mr.  Colles,  whose  opinions 


E e 


218 


OF  THE  TRUNK. 


are  entitled  to  the  utmost  respect,  thinks  that  surgeons 
err  in  regard  to  the  third  place,  and  that  the  stricture 
is  formed  there,  by  the  internal  margin  of  the  commence- 
ment of  the  _ femoral  sheath  instead  of  by  Gimbernat’s 
ligament.  He  says  that  this  orifice  remains  with  a sharp 
and  distinct  edge,  even  when  Gimbernat’s  ligament  is 
taken  completely  out  of  the  way,  and  that  the  edge  of 
Gimbernat’s  ligament,  supposed  to  constitute  this  stric- 
ture, stops  several  lines  short  of  the  Crural  Ring.  A 
dissection  performed  in  the  manner  that  he  recom- 
mends, is  unquestionably  in  favour  of  his  position. 

The  Anterior  Crural  Nerve  has  but  little  to  do  with 
this  dissection,  as  it  is  placed  beneath  the  fascia  iliaca, 
and  is  on  the  outside  of  the  artery. 


Section  IV. 

Of  the  Contents  of  the  Abdomen. 

For  common  examination,  a crucial  incision  through 
the  parietes  of  the  Abdomen,  from  the  sternum  to  the 
pubes,  on  the  left  of  the  navel,  and  from  one  side  to 
the  other,  on  a line  with  the  umbilicus,  but  a little  be- 
low it,  answers  very  well.  The  flaps,  thus  made,  be- 


CONTENTS  OF  THE  ABDOMEN.  219 

ing  turned  aside;,  and  kept  down,  the  viscera  of  the  ab- 
domen can  be  easily  seen. 

1.  The  Livee  is  in  the  Right  Hypochondriac  region; 
it  occupies  nearly  the  whole  of  it,  the  upper  part  of 
the  Epigastric,  and  the  right  superior  part  of  the  left 
Hypochondriac.  The  fundus  of  the  gall-bladder  pro- 
jects from  its  right  inferior  surface  beyond  its  anterior 
edge. 

2.  The  Stomach,  when  not  distended  much,  is 
confined  to  the  lower  half  of  the  Epigastric  region 
and  to  the  right  inferior  part  of  the  left  Hypochon- 
driac. 

3.  The  Spleen,  if  not  large,  recedes  into  the  back 
part  of  the  left  Hypochondriac  so  much,  that  to  be  seen 
it  must  be  drawn  out. 

4.  The  small  Intestines  lie  in  the  Umbilical,  Hypo- 

gastric, part  of  the  Iliac  regions,  and  also  in  the 
Pelvis,  when  the  viscera  of  the  latter  are  not  dis- 
tended. -1 

5.  The  Colon  begins  in  the  right  Iliac  region, 
passes  up  into  the  right  Lumbar  and  Hypochondriac, 
and  through  the  upper  part  of  the  Umbilical,  or  the 
lower  of  the  Epigasti’ic,  according  to  the  distention  of 
the  stomach;  it  then  gets  to  the  left  Hypochondriac, 


220 


OF  THE  TRUNK. 


being  commonly  higher  up  in  it  than  in  the  right  Hy- 
pochondriac; thence  it  passes  into  the  left  Lumbar  and 
Iliac,  forms  its  sigmoid  flexure,  and  dips  into  the  pelvis, 
where  it  is  continuous  with  the  rectum. 

6.  The  Omentum,  is  in  front  of  the  small  intestines, 
and  most  frequently  found  gathei-ed  up  in  the  Umbilical 
region.  If  it  be  not  diseased,  it  may  he  drawn  down- 
wards to  the  pelvis,  and  spread  out  so  as  to  conceal  all 
the  front  of  the  intestines. 

7.  The  Pan-creas,  is  at  the  back  of  the  Epigas- 
tric Region,  behind  the  stomach;  it  lies  horizontally, 
and  extends  from  the  right  of  the  spine  into  the  left 
Hypochondriac  region.  It  cannot  be  seen  without  cut- 
ting through  the  omentum,  and  turning  the  stomach  up- 
wards. 

8.  The  Kidneys  and  Capsulai  Renales  are  in  the 
Lumbar  Regions,  at  their  back  parts.  They  should 
not  be  sought  for  at  this  stage  of  the  dissection. 

It  is  useful  to  know  that  the  position  of  the  viscera 
of  the  abdomen  is  influenced  much  by  the  position  of 
the  body,  and  that  in  what  is  said  of  the  occupancy  of 
the  regions,  it  is  undei'stood  that  the  subject  is  on  his 
back.  When  one  stands  upright,  the  lumbar  ver- 
tebrae are  more  convex  in  front,  and  the  abdomen  moi  t- 
protuberant  below.  The  pehis  is  so  adjusted  that  the 


CONTENTS  OF  THE  ABDOMEN. 


221 


acetabula  are  nearly  in  a vertical  line  with  the  spine, 
which  gives  great  obliquity  to  the  superior  strait, 
mounts  the  sacrum  up  on  high,  and  brings  the  bodies 
and  rami  of  the  pubes  not  many  degrees  from  the  hori- 
zontal line.  Most  of  the  viscera  descend,  but  more 
particularly  the  liver,  which  being  no  longer  sustained 
by  the  false  ribs,  and  being  influenced  by  its  heavy 
inert  mass,  may,  in  many  cases,  be  felt  externally  along 
the  right  inferior  margin  of  the  thorax.  This  descent 
of  the  liver  will  be  according  to  the  degree  of  vacuity 
of  the  stomach,  intestines,  and  bladder. 

It  is  said  by  Winslow,  that  the  uneasiness,  pain,  and 
faintness  we  feel  in  a vacuity  of  the  stomach,  &c.  from 
the  want  of  food,  arise  from  the  liver  drawing  the 
diaphragm  downwards.  Portal  informs  us,  that  in 
order  to  ascertain  the  descent  of  the  liver  in  the  erect 
posture,  he  has  often  thrust  poignards  below  the  false 
ribs  of  dead  bodies,  and  that  he  has  invariably  found 
the  wounds  much  higher  up,  than  when  they  were 
inflicted  in  the  horizontal  posture. 

It  should  be  well  recollected  that  the  abdominal 
cavity  is  always  full,  there  being  no  unoccupied  space 
in  it ; hence,  whenever  any  viscus  has  an  inordinate 
growth,  or  a tumour  forms  on  it,  or  an  effusion  occurs 
in  the  peritoneal  cavity,  the  other  viscera  are  en- 
croached upon.  In  a treatment  for  sickness,  when  the 
stomach  and  bowels  have  been  evacuated  by  low  diet 
and  purging,  air  supplies  the  place  of  more  solid  matter, 
and  keeps  them  distended.  It  is  indeed  exceedingly 


222 


OF  THE  TRUNK. 


rare  to  find  the  small  intestines  contracted;  in  the  large, 
it  is  more  common. 

Having  become  generally  informed  on  the  viscera  of 
the  abdomen,  by  repeated  handling,  we  should,  in  the 
next  place,  proceed  to  an  examination  of  their  forms 
and  structure. 

The  Peritoneum  is  a thin,  delicate,  semitranspa- 
rent membrane,  very  extensible,  and  spread  out  so  as 
to  line  the  cavity  of  the  abdomen,  and  to  give  an  exter- 
nal covering  to  the  greater  number  of  its  viscera.  In 
man,  it  is  a complete  sac,  having  no  hole  in  it;  but  in 
woman,  its  cavity  communicates  externally  through  tlie 
fallopian  tubes.  It  has  a double  use;  in  consequence  of 
covering  the  viscera,  it  is  so  reflected  from  them  to  the 
sides  of  the  abdomen,  that  its  processes  keep  the  viscera 
in  their  proper  places,  and  therefore  answer  as  liga- 
ments. Again,  its  internal  surface  being  smooth, 
highly  polished,  and  continually  lubricated  by  a thin 
albuminous  fluid  corresponding  with  the  synovial  mem- 
brane of  the  joints,  the  motions  which  the  viscera  have 
upon  each  other  in  exercise,  and  in  the  peristaltic 
movements  of  the  bowels,  are  much  facilitated. 

The  manner  in  which  a double  night- cap  is  applied 
to  the  head,  will  afford  the  easiest  conception  of  the 
reflections  of  the  peritoneum.  If  there  were  only  one 
viscus  in  the  belly,  and  that  of  a somewhat  regular  out- 
line, as  the  spleen,  the  comparison  would  be  rigid,  and 
perfectly  appreciable.  One  part  of  the  cap  is  close  to 


CONTENTS  OF  THE  ABDOMEN. 


223 


the  head,  and  compares  with  the  peritoneal  coat  of  the 
spleen ; the  other  is  loose,  and  is  equivalent  to  the  peri- 
toneum, where  it  is  in  contact  with  the  parietes  of  the 
belly.  It  is  also  evident  from  this,  that  none  of  the 
viscera  can  be  said  to  be  within  the  cavity  of  the  peri- 
toneum; that  they  are  all  on  its  outside;  and  that  a 
viscus,  in  getting  a coat  from  the  peritoneum,  merely 
makes  a protusion  into  its  cavity.  Starting  with  this 
most  simple  proposition,  it  is  easy  to  conceive  of  a 
second,  a third  body,  and  so  on,  deriving  an  external 
coat  from  a protusion  into  the.  same  sac.  Admitting 
these  bodies  to  be  spheres,  the  proposition  is  immedi- 
ately intelligible  ; and  as  a last  step  from  it,  the  idea  is 
not  rendered  much  more  complex  by  substituting  any 
bodies,  even  the  most  irregular  in  form,  for  these 
spheres.  Such,  then,  is  the  fact,  in  regard  to  the 
stomach,  intestines,  &c. ; they  all,  with  exceptions  to 
be  stated,  derive  an  external  coat  from  the  peritoneum. 

The  reflections  of  peritoneum  forming  the  ligaments 
of  the  liver  will  be  best  described  in  connexion  with 
that  viscus.  Its  reflections  over  the  viscera  of  the 
pelvis  will  be  described  with  them ; we  will  merely  say 
for  the  present  that  it  covers  the  upper  and  back  part 
of  the  urinary  bladder,  and  is  reflected  from  it  to  the 
rectum. 

The  reflections  for  immediate  study  are  the  Omen- 
tums.  Fatty  Appendages  of  the  Colon,  the  Mesentery 
and  the  Mesocolon, 


224 


OF  THE  TRUNK. 


1.  There  are  four  Omentums.  Omentum  Minus  or 
Hepatico  Gastricum,  Omentum  Majus  or  Gastro-Coli- 
cum;  Omentum  Gastro-Splenicum,  Omentum  Colicum. 

a.  The  Omentum  Minus  extends  in  a transverse 
direction  from  the  transverse  fissure  of  the  liver  where 
the  capsule  of  Glisson  is  connected  to  the  latter ; from 
the  right  of  the  lobulus  spigelii  at  the  posterior  half  of 
the  umbilical  fissure ; and  from  the  inferior  face  of  the 
diaphragm,  to  the  lesser  curvature  of  the  stomach  from 
the  end  of  the  oesophagus  to  the  pylorus  and  duodenum. 
It  is  composed  of  two  laminae  which,  near  the  stomach, 
are  separated  by  the  coronary  vessels.  It  has  always 
but  an  inconsiderable  quantity  of  fat  in  it. 

h.  The  Omentum  Majus,  or  Gastro-Colicum,  is 
an  irregular  quadrilateral  membrane  having  its  base 
upwards.  The  latter  is  fixed  anteriorly  to  the  gi’eater 
curvature  of  the  stomach,  and  posteriorly  to  the  trans- 
verse arch  of  the  colon.  It  hangs  loose  in  its  infei’ior 
part,  and  is  sometimes  found  spread  over  the  intestines 
as  low  as  tlie  pelvis ; it  is,  therefore,  not  improperly 
compared  to  an  apron.  On  its  right  side  it  is  continued 
into  the  omentum  colicum,  and  on  the  left  into  the  gas- 
tro-splenicum.  It  consists  of  two  lamin®,  the  anterior 
is  fixed  to  the  stomach,  the  posterior  to  the  colon. 
Each  of  these  laminae  again  is  composed  of  two,  so  that 
it  may  be  compared  to  two  bags,  one  within  the  otlier, 
connected  at  their  upper  or  open  end  to  the  stomach 


CONTENTS  OF  THE  ABDOMEN. 


225 


and  colon.  The  internal  and  external  bags  are  very- 
separable  above,  but  below  they  are  closely  united.  In 
corpulent  subjects  a great  deal  of  fat  is  found  in  this 
membrane. 

By  searching  for  the  neck  of  the  gall-bladder,  we  shall 
firid  near  it  under  the  capsule  of  Glisson,  the  Foramen  of 
Winslow,  an  opening  which  conducts  into  the  bag  of 
the  omentum  majus.  It  is  large  enough  to  admit  easily 
two  fingers.  By  detaching  the  omentum  majus  from 
the  stomach,  and  turning  it  down,  we  shall  see  the  na- 
ture of  its  cavity,  its  extent,  and  all  the  parts  constitu- 
ting its  parietes.  This  cavity  is  bounded  above,  by  the 
omentum  minus  and  stomach,  in  front  by  the  two  laminm 
sent  from  the  stomach;  behind  and  below,  by  these 
laminse  being  reflected  upwards  and  joining  the  colon, 
and  posteriorly  and  above,  by  the  upper  lamina  of  the 
mesocolon  which  is  extended  to  the  lobulus  spigelii. 
By  a little  reflection  it  will  be  understood  that  I 
have  described  an  uninterrupted  cavity,  beginning  at 
the  lobulus  spigelii  by  the  omentum  minus,  and  termina- 
ting with  the  lobulus  spigelii  by  the  upper  lamina  of  the 
mesocolon.  It  is  acknowledged  on  all  sides  to  be  one 
of  the  most  obscure  propositions  in  descriptive  anatomy, 
even  when  the  subject  is  before  a young  student.  If 
is  a point  well  worth  mastering,  as,  when  this  is  ac.- 
complished  all  other  difliculties,  in  studying  the  reflec- 
tions of  the  peritoneum,  are  much  diminished. 

F f 


226 


OF  THE  TRUNK. 


c.  The  OMENtuM  CoEicuM  is  a prolongation  of  the 
omentum  majus,  from  the  internal  side  of  the  right 
ascending  colon,  and  from  the  adjacent  part  of  the  trans- 
verse. It  is  filled  with  fat  from  the  same  causes  as  the 
preceding,  but  consists  of  only  two  single  laminse. 

d.  The  Omentum  Gastro-Splenicum  is  that  pro- 
cess of  peritoneum  which  extends  from  the  large  ex- 
tremity of  the  stomach  to  the  spleen  ; it  may  be  consi- 
dered a prolongation  of  the  omentum  majus,  and  en- 
closes in  its  duplicature  the  arteries  and  veins  called 
Vasa  Brevia. 

e.  The  Appendiculje  Epiploicje  are  little  pro- 
cesses of  peritoneum,  filled  with  fat,  appended  at  irre- 
gular intervals  to  the  anterior  sides  of  the  cjEcum,  co- 
lon, and  the  upper  part  of  the  rectum. 

The  Mesenterium  is  extended  obliquely  across  the 
spine  from  a line  parallel  with  the  second  lumbar  ver- 
tebra to  the  right  iliac  fossa.  This  part,  called  its  root 
in  the  adult,  is  about  six  inches  in  length  and  flat,  but 
the  inferior  edge,  which  is  loose  and  pendulous  having 
the  intestines  connected  with  it,  has  its  circumference 
increased  to  many  feet,  which  causes  it  to  lie  in  folds. 
The  mesentery  attaches  the  left  extremity  of  the  duo- 
denum, the  jejunum,  and  ileum  to  the  spine.  It  con- 
sists of  two  laminae  of  peritoneum  separated  by  the 
mesenteric  arteries  and  veins,  the  lacteal  glands  and 


CONTENTS  OF  THE  ABDOMEN. 


227 


vessels,  and  the  nerves  derived  from  the  solar  plexus. 
There  is  also  some  fat  between  them. 

The  Mesocolok  fixes  the  large  intestine  to  the 
back  of  the  abdomen.  The  posterior  part  of  the  cae- 
cum b,eing  devoid  of  peritoneal  coat,  is  of  course  in 
contact  with  the  internal  iliac  muscle  and  is  tied  down 
to  it.  The  eolon  in  the  right  and  left  lumbar  regions 
is  also  for  the  most  part  immoveably  fixed,  the  mesoco- 
lon being  there  of  very  little  length;  but  the  transverse 
mesocolon  is  long,  and  forms  a complete  and  moveable 
partition  between  the  upper  and  the  lower  parts  of  the 
abdomen,  which  permits  the  colon  to  ascend  and  de- 
scend according  to  the  distention  of  the  small  bowels  and 
stomach.  In  the  left  iliac  region  the  mesocolon  is  elon- 
gated so  much  as  to  allow  very  free  motion  to  the  sig- 
moid flexure  of  the  gut,  and  continues  into  the  meso- 
rectum. 

Of  the  Ventriciilus,  or  Stomach. 

The  stomach  is  a sac  curved  considerably.  As  was 
stated,  it  is  in  the  epigastric  region,  in  contact  above 
with  the  diaphragm,  with  the  left  lobe  of  the  liver  and 
the  lobulus  spigelii;  on  the  left  with  the  spleen ; behind 
with  the  pancreas ; and  below  with  the  colon  and  meso- 
colon. The  stomach  has  a very  great  obliquity  in  its 
situation,  the  right  extremity  being  much  lower  down 
than  the  left. 


228 


OF  THE  TRUNK. 


The  exterior  of  the  stomach  presents  two  facesj  two 
orifices,  two  curvatures,  and  two  extremities. 

When  the  stomach  is  nearly  empty  it  becomes  some- 
what flattened,  and  then  exhibits  an  anterior  and  a pos- 
terior face ; in  a state  of  distention,  the  first  looks  ob- 
liquely upwards,  and  the  latter  obliquely  downwards. 
The  angle,  formed  with  the  oesophagus,  is  increased 
according  to  the  degree  of  distention. 

The  orifices  are  the  Pyloric  and  the  Cardiac.  Tlie 
pyloric  viewed  externally  presents  nothing  remarkable 
but  seems  to  be  a continuation  of  the  right  extremity 
of  the  stomach  into  the  duodenum.  The  cardiac,  form- 
ed by  the  junction  of  the  oesophagus  with  it,  is  at  the 
upper  edge  of  the  stomach,  some  distance  from  the  ex- 
ti’eme  left. 

The  curvatures  are  the  Great  and  Small.  The  fii-st 
includes  the  great  extremity  and  the  inferior  edge  of  the 
stomach  to  the  pylorus ; the  smafi  is  the  upper  margin 
between  the  orifices. 

The  Tuber  or  great  extremity  of  the  stomach  is  tlie 
part  to  the  left  of  a vertical  plane  passing  through  the 
cardia  ; it  is  smaller  in  proportion  in  children  than  in 
adults. 

The  stomach  consists  of  four  laminae.  The  external 
is  peritoneal,  and  derived  from  the  separation  of  the 
two  leaves  of  the  omentum  minus.  The  second  is  mus- 
cular, its  thickness  is  inconsiderable,  and  the  fibres 
which  compose  it  are  remarkably  pale ; they  are  best 
seen  near  the  cardia  and  at  the  pylorus.  At  the  latter 


CONTENTS  OF  THE  ABDOMEN. 


229 


they  are  collected  into  a ring  of  considerable  thickness, 
which  making  a marked  prominence  internally,  helps  to 
constitute  the  valve  of  the  pylorus.  The  muscular  fibres 
go  in  three  directions.  The  first  being  longitudinal,  are 
continued  from  similar  ones  of  the  oesophagus,  and  ex- 
tend to  the  pyloric  orifice.  The  principal  part  of  them 
is  collected  into  two  bands,  the  thicker  of  which  passes 
along  the  lesser  curvature,  and  the  thinner  along  the 
greater.  The  second  set  of  muscular  fibres  surrounds 
the  stomach  by  segments  of  circles,  none  of  them  going 
completely  around.  It  is  this  set,  in  an  especial  manner 
which  assists  in  the  pyloric  valve.  The  third  and  most 
profound  set  of  muscular  fibres  is  oblique,  and  forms 
two  large  bands.  One  is  extended  from  the  left  side  of 
the  cardia  over  the  anterior  and  posterior  faces  of  the 
stomach,  and  the  other  is  prolonged  from  the  right  side 
of  the  same  orifice  over  the  great  extremity  also  before 
and  behind,  where  it  supplies  the  want  of  transverse  or 
circular  fibres. 

The  third  coat  of  the  stomach  consists  of  a very 
dense  compact  short  cellular  membrane,  which  unites 
the  muscular  and  internal  coat,  and  conducts  the  vessels 
and  nerves  to  the  latter. 

The  fourth  or  Internal  Coat  of  the  stomach,  called, 
also  the  Mucous  or  Villous,  is  of  a light  red.  It  is  form- 
ed of  villosities  like  velvet,  which  terminate  at  the 
cardiac  orifice;  it  is  thrown  into  very  irregular  folds, 
according  to  the  degree  of  contraction  of  the  stomach, 
and  by  its  reflection  over  the  circular  plane  of  fibres  at 
the  pylorus  increases  the  projection  of  the  valve. 


OF  THE  TRUNK, 


:^30 


Of  the  Intestinal  Canal. 

This  Canal  is  from  thirty  to  thirty -five  feet  long, 
in  the  human  subject,  and  extends  from  the  Pylorus  to 
the  Anus.  It  consists  of  two  portions,  the  longer  forming 
four-fifths  of  the  whole,  extends  from  the  stomach  to 
the  ileo-cascal  valve,  the  other  from  this  latter  to  the 
anus.  The  first  is  Intestinum  Tenue,  the  second  Intes- 
tinum  Crassum.  This  canal  like  the  stomach  consists  of 
four  coats,  peritoneal,  muscular,  nervous,  and  \fillous. 

The  small  Intestine,  or  Iktestinum  Texue,  is  divid- 
ed, somewhat  artificially,  by  anatomists,  into  three  parts. 
Duodenum,  Jejunum,  and  Ileum.  The  first,  from 
peculiar  civcumstances,  is  perhaps  named  properly 
enough;  but  several  distinguished  men,  as  Chaussief, 
Soemmering,  &c.  think  that  the  two  last  may  be  treat- 
ed of  more  advantageously,  under  the  name  of  Mesen- 
teric Portion  of  Small  Intestine. 

The  Duodenum  deduces  its  name  from  its  length, 
which  has  been  fixed  at  twelve  fingers  breadth.  It  is 
also  called  Ventriculus  Succenturiatus.  Beginning  at 
the  pylorus,  it  passes  to  the  right,  and  upwards,  to- 
wards the  neck  of  the  gall-bladder;  it  then  forms  a right 
angle,  and  passes  downwards  before  the  right  kidney, 
to  the  third  lumbar  vertebra  between  the  two  laminae  of 
the  Mesocolon  on  the  right  side.  Here  it  forms  a 


CONTENTS  OF  THE  ABDOMEN. 


231 


round  elbow,  and  crosses  the  spine  obliquely  upwards, 
making  it§  appearance  to  the  left  of  the  second  lumbar 
vertebra,  where  it  is  continued  into  the  mesenteric  por- 
tion of  intestine. 

The  head  of  the  Pancreas  lies  in  the  bend  of  the 
duodenum,  and  fixes  it  firmly  just  there.  The  first 
part,  where  it  emanates  from  the  pylorus,  is  moveable, 
and  covered  with  peritoneum  j the  second  and  third 
portions  are  between  the  laminae  of  the  mesocolon,  but 
have  no  peritoneal  coat  j and  the  termination  is  both 
moveable,  and  has  a peritoneal  coat.  The  partial 
deficiency  of  peritoneal  coat,  is  said  to  be  the  cause  why 
the  duodenum  is  susceptible  of  an  enlargement,  in  some 
cases,  but  little  inferior  to  the  stomach. 

The  muscular  coat  of  this  intestine  consists  of  two 
planes  of  fibres,  the  external  one  longitudinal,  the  other 
circular  and  much  the  most  numerous.  Beneath  is  the 
coat  of  cellular  membrane  connecting  it  with  the  mu- 
cous or  villous  coat.  The  internal  coat  is  reddish, 
tinged  with  bile,  and  occupied  by  a great  number  of 
rugSB  or  folds.  They  are  transverse  and  oblique,  very 
near  each  other,  about  three  lines  broad,  and  as  promi- 
nent in  the  distended  as  the  undistended  gut ; these 
constitute  the  Valvulse  Conniventes.  Many  mucous 
follicles  exist  in  this  intestine,  and  mucous  glands,  call- 
ed Glandulse  Brunneri;  the  latter  are  particularly  ac- 
cumulated about  the  pyloric  orifice.  It  is,  in  its  pos- 
terior part,  about  four  inches  from  the  stomach,  that 


232 


OF  THE  TRUNK. 


the  orifices  of  the  pancreatic  and  hepatic  ducts  are 
found. 

The  Inferior,  or  Mesenteric  portion  of  the  Intesti- 
num  Tenue,  has  the  same  coats  with  the  preceding. 
In  the  upper  two-fifths,  called  Jejunum,  the  valvulse 
conniventes  are  numerous,  and  arranged  transversely; 
but  in  the  lower  three-fifths,  called  Ileum,  they  gra- 
dually diminish,  and  near  its  terminatidn,  cease  en- 
tirely. There  is  a gradual  diminution  of  the  diameter 
of  this  intestine  from  above  downwards.  From  the 
length  of  the  mesentery,  great  latitude  of  motion  is 
allowed  to  it.  It  presents  a very  irregular  and  con- 
fusing appearance  at  first,  but  one  soon  becomes  accus- 
tomed to  its  course  and  convolutions : and  then  its  com- 
mencement and  termination  are  as  readily  found  as 
those  of  any  other  organ.  It  is  probable  that  in  the 
distentions  of  this  bowel,  the  peritoneal  coat  does  not 
stretch  much,  as  the  laminae  of  mesentery  are  loosely 
applied  against  each  other  where  they  join  the  intes- 
tine, and  are  separated  in  its  distentions,  as  far  as  tlie 
first  row  of  the  mesenteric  arches  of  blood-vessels. 
Cases  are  reported,  in  which  it  has  had  appendiculae 
epiploicEe  and  cul-de-sacs  projecting  from  its  sides.  I 
have  never  seen  the  former,  but  of  the  latter,  a spe- 
cimen was  presented  to  me  a few  years  ago,  taken  from 
a child  by  the  late  Dr.  Edward  Barton  ; and  another 
specimen  now  belongs  to  the  Wistar  Museum,  obtained 
in  the  dissecting  rooms. 

The  mucous  or  internal  coat  of  the  Intestinum  To- 


CONTENTS  OF  THE  ABDOMEN. 


233 


nue,  differs  from  that  of  the  stomach,  in  resembling 
more,  the  downy  cuticle  of  an  unripe  peach.  The  little 
pT’ojections  from  it,  are  called  Villi;  on  the  surfaces  of 
which,  open  the  orifices  of  the  lacteals.  ft  abounds 
with  mucous  follicles  and  glands;  the  latter,  called 
GlandulsB  Peyeri,  are  particularly  conspicuous  near  its 
junction  with  the  mesentery. 

The  large  Intestine,  or  the  Intestinum  Crassum,  has 
already  been  explained  in  regard  to  its  course.  It  is 
more  obviously  a conical  tube  than  the  small  intestine, 
being  very  large  at  its  commencement  when  inflated, 
and  diminishing  much  to  the  lower  end  of  the  sigmoid 
flexure.  Anatomists  call  its  commencement,  or  that 
part  below  the  ileo-colic  valve.  Caecum  or  Caput  Coli ; 
and  the  remaining  portion,  which  is  by  far  the  longest, 
the  Colon,  until  it  reaches  th,e  pelvis,  when  it  becomes 
Rectum. 

The  Caput  Coli  is  about  two  inches  in  length,  and  is 
fixed  to  the  iliac  fossa  by  peritoneum  and  loose  cellular 
membrane.  At  its  inferior  extremity,  towards  the  left 
is  the  Appendix  Vermiformis,  a blind  cavity  of  four 
coats,  about  four  inches  long,  and  of  the  size  of  a tur- 
key quill,  enclosed  in  a duplicature  of  peritoneum.  It 
floats  loose,  and  occasionally  becomes  a cause  of  mis- 
chief, by  getting  around  the  ileum,  and  inflaming, 
by  which  it  adheres  and  produces,  in  some  measure, 
strangulation.  The  Colon  makes  a large  sweep  around 
the  abdomen,  and  in  passing  under  the  gall-bladder, 
touches  it,  and  thus  becomes  tinged  with  bile  after 

G g 


234 


OF  THE  TRUNK. 


death.  In  its  transverse  course,  we  frequently  find  it 
passing  through  the  umbilical  region. 

The  coats  of  the  Intestinura  Crassum,  correspond  in 
number  with  those  of  the  small  intestine ; but  there  are 
some  differences  in  structure.  The  longitudinal  mus- 
cular fibres  are  much  more  conspicuous ; they  are  col- 
lected into  three  bands,  which  commence  at  the  head 
of  the  colon,  and  extend  to  the  upper  part  of  the  rec- 
tum ; one  is  superior,  another  inferior,  and  a third  an- 
terior. They  are  equidistant  from  each  other.  These 
longitudinal  bands  produce  the  cells  of  the  colon,  by 
drawing  its  extremities  nearer  together.  The  cells 
are  separated  laterally,  by  partitions  or  butresses  form- 
ed of  a doubling  of  all  the  coats  of  the  intestine;  where- 
as in  the  small  intestine,  the  valve  or  doubling  belongs 
exclusively  to  the  mucous  membrane.  These  cells  are 
not  so  numerous  or  well  formed  in  the  sigmoid  flexure 
and  thereabouts ; the  channel  is  therefore  more  open 
and  unobstructed.  By  dividing  the  longitudinal  bands, 
the  cells  are  removed,  and  the  intestine  elongates  con- 
siderably. 

The  Ileo  Colic  Valve,  or  valve  of  Bauhen,  or  Tulpius, 
is  a great  curiosity  in  the  anatomical  structure  of  this 
gut.  The  ileum  runs  into  the  left  side  of  the  colon, 
and  continues  its  cellular  and  mucous  coat  into  the  cor- 
responding coats  of  the  colon,  the  muscular  coat  of  the 
latter  being  simply  parted.  To  prevent  the  furtlier 
separation  of  the  muscular  fibres,  a little  ligamentous 
arrangement,  called  Retinacula  Morgagni,  prevails  at 


CONTENTS  OF  THE  ABDOMEN. 


235 


each  end.  When  viewed  from  within  the  colon,  the 
opening  appears  as  a transverse,  or  very  narrow  ellip- 
tical slit,  established  by  two  lips,  the  superior  broader 
than  the  inferior.  They  meet  like  the  gates  of  the 
common  ship-dock  or  hydraulic  lock;  and  from  being 
placed  transversely,  in  regard  to  the  cavity  of  the 
intestine,  every  distention  which  the  latter  may  suffer 
from  the  accumulation  of  faeces,  has  a tendency  to  force 
this  valve,  and  will,  by  stretching  its  extremities,  make 
the  lips  tighter  and  more  resisting. 

The  internal  coat  of  the  large  intestine  differs  very 
materially  from  that  of  the  small.  It  has  few  or  no  villi. 
Near  its  commencement,  it  preserves  the  fungous  ap- 
pearance of  the  stomach,  but  about  the  sigmoid  flexure, 
it  is  a plain  smooth,  surface.  A great  many  mucous  folli- 
cles and  mucous  glands  are  in  it.  It  has  lacteals,  but 
they  are  not  so  numerous. 

The  Rectum  will  be  described  with  the  Pelvis. 

Of  the  Liver ^ {Hepar  Sive  Jecur.) 

Its  position  in  the  abdomen  and  the  space  it  occupies 
have  been  mentioned.  It  is  placed  in  the  following 
relations;  above,  it  is  in  contact  with  the  concavity 
of  the  diaphragm;  below,  are  the  Omentum  Minus, 
the  Stomach,  and  the  Transverse  Arch  of  the  Colon; 
behind,  are  the  Vertebral  Column  and  the  Ascending 
Cava.  When  we  lie  on  the  right  side  it  is  sustained 
by  the  ribs  in  the  easiest  posture;  when  on  the  left  it 


236 


OF  THE  TRUNK.' 


sometimes  occasions  uneasiness  by  pressing  on  the 
stomach;  and  when  on  the  back  it  compresses  the 
ascending  cava. 

Its  form  is  happily  compared,  by  Professor  Chaussier,. 
to  the  section  of  an  ovoid  made  in  the  direction  of  its 
greatest  diameter,  the  thick  end  being  to  the  right  side. 
It  is  fastened  in  its  situation  by  the  following  reflections 
of  the  peritoneum.  From  the  centre  of  the  diaphragm, 
and  extending  from  the  umbilicus  backwards  to  near  the 
ascending  cava,  is  the  Falciform  or  Suspensory  Liga- 
ment, consisting  of  two  laminae ; it  is  thickened  at  its 
anterior  edge  by  what  was  once  umbilical  vein  in  the 
foetus,  but  is  now  converted  into  a fibrous  substance 
called  Round  Ligament.  This  falciform  ligament  di- 
vides the  upper  surface  of  the  liver  unequally  into  two, 
the  left  being  the  smaller;  it  also  penetrates  a notch  in 
the  anterior  edge  of  the  liver.  On  the  right  of  the  fal- 
ciform process,  and  extending  from  the  diaphragm  to 
the  posterior  edge  of  the  liver,  is  the  Right  Lateral 
Ligament;  to  the  left  of  the  same  process,  and  also  ex 
tending  from  the  diaphragm  to  the  back  edge  of  the 
liver,  is  the  Left  Lateral  Ligament;  and  that  portion 
of  peritoneum  concerned  in  the  union  of  these  three 
ligaments  forms  the  Coronary  Ligament.  Within  the 
circumference  of  the  coronary  ligament  the  sui’face  of 
the  liver  is  not  covered  by  peritoneum,  and  it  is  attach- 
ed to  the  diaphragm  by  loose  cellular  substance. 

The  precise  shape  of  the  liver  is  best  seen  in  one  rc 
moved  from  the  body.  Its  colour  is  a reddish  brown 


CONTENTS  OF  THB  ABDOMEN.  237 

The  following  parts  are  noticed  by  anatomists : its  upper 
surface,  its  lower  surface,  its  right  extremity,  its  left 
extremity,  its  anterior  edge,  and  its  posterior  edge. 

The  upper  surface  is  uniformly  convex,  and  pre- 
sents nothing  remarkable  but  its  unequal  division  by 
the  suspensory  ligament. 

The  lower  surface  is  very  irregularly  concave,  and 
on  it  are  the  following  appearances:  From  the  front  to 
the  back  edge  is  a deep  fissure  corresponding,  in  situ- 
ation, with  the  suspensory  ligament  above,  and,  with 
it,  giving  occasion  to  divide  the  liver  into  right  and 
left  lobes.  This  is  the  Sulcus  Umbilicalis,  occupied 
in  front  by  what  was  umbilical  vein,  and  in  the  rear 
by  what  was  ductus  venosus,  both  vessels  in  the  adult 
being  in  a ligamentous  state.  Crossing  this  fissure  at 
right  angles,  passing  from  the  left  lobe,  for  some  dis- 
tance into  the  right,  and  occupying  about  the  middle 
third  or  fourth  of  the  long  diameter  of  the  liver,  is  the 
Sulcus  Transversalis.  In  it  are  the  Vena  Portarum,  He- 
patic Artery,  and  Ducts.  TheLobulus  Spigelii  or  pos- 
terior lobe  is  at  the  back  of  the  liver  just  to  the  right 
of  the  posterior  part  of  the  sulcus  umbilicalis.  It  is 
like  a ridge  and  terminates  forwards  in  a papillae  which 
is  one  of  the  portae  of  the  liver;  to  the  right,  the 
lobulus  spigelii  sends  off  a small  process  which  unites  it 
with  the  greater  lobe  of  the  liver,  and  is  called  the  Lo- 
bulus Caudatus.  On  the  front  of  the  inferior  surface 
between  the  fore  part  of  the  umbilical  fissure  and  the 
gall-bladder  is  a flat  rising,  the  Lobulus  Anonymus  or 


238 


OF  THE  TRUNK. 


Quartus;  its  posterior  extremity,  opposite  to  the  an- 
terior of  the  lobulus  spigelii,  is  the  second  pula  or  porta 
of  the  liver. 

The  right  extremity  of  the  liver  is  very  thick  and 
almost  fills  the  right  hypochondriac  region,  but  the  left 
tapers  to  a very  thin  edge.  The  posterior  border  or 
edge  is  thick,  but  the  anterior  is  thin.  The  former  is 
marked  by  a short  large  sulcus  for  the  ascending  vena 
cava,  sometimes  converted  into  a complete  canal ; the 
latter  only  has  the  notch  for  the  suspensory  ligament 
already  mentioned. 

Besides  the  peritoneal  coat,  the  liver  has  a second, 
which  covers  its  whole  exterior  surface,  adhering  very 
closely  to  the  peritoneum  on  one  side,  and  to  the  liver 
on  the  other ; it  penetrates  into  the  substance  of  the 
liver,  and  holds  together  its  gi’anulated  structure.^ 
This  tunic  is  easily  seen  by  stripping  off  the  peritoneum  , 
and  in  parts  which  naturally  are  left  uncovered  by  the 
latter. 

The  Blood-vessels  are  of  three  kinds.  The  two 
first  bring  the  blood  to  the  liver,  the  third  takes  it 
away.  The  hepatic  artery,  a branch  of  the  cceliac, 
after  having  detached  some  smaller  ramifications,  gets 
to  the  transverse  fissure  of  the  liver  and  divides  into 
three  branches ; one  to  the  right  lobe,  one  to  the  left 
lobe,  and  another  to  the  Lobulus  Spigelii ; they,  how 

* See  ScEimnering'S  Anatomy,  Laennec^s  .Tonrnal  de  Med-’- 


cine. 


CONTENTS  OF  THE  ABDOMEN. 


239 


ever,  subdivide  before  they  reach  the  substance  of  the 
liver.  These  branches  are  between  the  sinus  porta- 
rum  and  the  biliary  ducts.  The  vena  portarum  is 
formed  from  the  union  of  all  the  veins  of  the  intes- 
tines, stomach,  pancreas,  and  spleen,  forming  a single 
trunk  about  three  inches  long.  It  gets  to  the  trans- 
verse fissure  of  the  liver,  over  the  duodenum  and 
under  the  pancreas,  and  immediately  sends  off,  at  right 
angles,  two  branches  which,  collectively,  are  called  the 
sinus  of  the  vena  portarum.  -The  right  branch,  being 
the  shortest  and  largest,  is  distributed  to  the  great  right 
lobe ; the  left  sends  its  branches  to  the  lobulus  spigelii, 
anonymus,  and  left  lobe. 

At  the  bottom  of  the  transverse  fissure  is  a lamellat- 
ed  fibrous  cellular  tissue,  closely  adhering  to  the  liver, 
which  accompanies  the  vena  portarum,  the  hepatic 
artery,  and  hepatic  duct  in  their  ramifications,  form- 
ing sheaths  for  them  as  they  go  off  successively.  As 
the  branches  of  these  tubes  keep  togetlier  they  are 
united  by  the  cellular  sheaths.  Glisson  believed  these 
sheaths  to  be  muscular  and  they  have  obtained  the 
name  of  his  capsule ; and,  indeed,  the  capsule,  is  ge- 
nerally spoken  of  as  lying  on  the  aforementioned  ves- 
sels, even  before  they  reach  the  liver.  The  hepatic 
veins  arise  from  the  capillary  extremities  of  the  hepa- 
tic artery  and  vena  portarum ; there  are  three  princi- 
pal trunks  of  them  coming,  two  from  the  right  and  one 
from  the  left  lobe  of  the  liver,  and  emptying  into  the 
ascending  cava,  just  below  the  diaphragm ; there  are 
also,  five  or  six  little  trunks,  coming  from  the  the  pos- 


240 


OF  THE  TRUNK. 


terior  surface  of  the  liver,  and  the  lobulus  spigelii,  which 
empty  into  the  ascending  cava  below  the  other.  The 
hepatic  veins  have  no  valves,  and  may,  in  a section  of 
the  liver,  be  readily  distinguished  from  other  vessels 
by  their  lonely  course,  by  their  crossing  the  others  at 
right  angles,  and  by  their  thinness.  All  of  thes'e  vessels 
of  the  liver  are  remarkable  for  the  number  of  their  anas- 
tomoses and  the  facility  of  their  communication  with 
each  other.  A minute  injection  of  either  pervades  all 
parts  of  the  liver,  and  the  injection  if  persevered  in  will 
fill  all  the  other  vessels.  By  tearing  the  substance  of 
the  liver  a good  view  of  its  organization  may  be  ob- 
tained ; it  will  then  be  seen  to  be  composed  of  an  im- 
mense number  of  spherical  or  polyedrical  grains  united 
to  each  other  by  the  cellular  tissue  of  the  internal  coat. 
These  grains  contain  the  essential  and  ultimate  points 
of  the  glandular  arrangement,  the  anastomoses  of  the 
vessels  are  formed  in  them,  and  also  the  capillaries  of 
the  hepatic  duct ; but  what  the  final  organization  is 
by  which  bile  is  formed  is  yet  doubtful. 

The  nerves  of  the  Liver  will  be  mentioned ^at  an- 
other place,  along  with  the  general  account  of  such  as 
belong  to  the  Abdomen. 

The  Gall-bladder,  (Vesicula  sive  Cistis  Fellea,)  is 
fixed  on  the  inferior  surface  of  the  great  lobe,  it\  a 
broad  shallow  fossa  for  the  purpose.  It  is  not  placed 
in  the  line  of  the  short  diameter  of  the  liver,  but  some- 
what obliquely,  its  anterior  end,  which  reaches  to  t!ie 
edge  of  the  liver,  being  turned  to  the  right,  and  its 


CONTENTS  OF  THE  ABDOMEN. 


241 


posterior,  which  goes  to  the  transverse  fissure,  being 
turned  towards  the  left.  Its  shape  is  conical,  the  base 
being  rounded  off*  and  the  apex  curved ; the  body  di- 
minishes gradually  to  the  apex.  The  gall-bladder  has 
three  coats;  the  peritoneal  is  only  partial,  from  the 
upper  face  of  the  gall-bladder  being  in  contact  with 
the  liver.  The  second  coat  is  cellular  membrane,  in 
which  ramifies  a great  number  of  blood-vessels  and 
lymphatics.  The  third  may  be  considered  a continuation 
of  the  mucous  coat  of  the  intestines,  but  has  some  pecu- 
liarities. On  its  internal  face,  it  is  thrown  into  irre- 
gular tortuous  folds  or  wrinkles  of  extreme  delicacy,  in 
the  intervals  of  which  are  many  round  or  polyedrous 
cells ; some  small,  others  a line  and  a half  deep, 
particularly  about  the  middle  of  the  body.  In  the 
neck  or  apex  of  the  gall-bladder,  from  three  to  seven 
elevated  semilunar  folds  are  formed,  of  the  internal 
membrane. 

The  gall-bladder  and  the  contiguous  parts,  after 
death,  are  always  tinged  with  bile,  which  does  not  oc- 
cur in  tlie  living  body.  I have,  however,  in  one  case 
in  our  dissecting  rooms,  seen  a gall-bladder  in  an  old 
African  woman,  filled  by  a pint  of  very  fluid  watery 
greenish  bile,  and  the  tissue  of  which  had  been  so  lax, 
that  a quart  or  more  of  the  same  secretion  had  perco- 
luted  into  the  abdomen  probably  before  death. 

The  Hepatic  Duct  arises,  by  very  delicate 
branches,  from  the  granuli  of  the  Liver.  These 

Hh 


242 


OF  THE  TRUNK. 


branches  are  united  into  three  or  four  tmnks,  in  the 
transverse  fissure,  which  trunks  again  unite  into  one 
about  the  size  of  a writing^quil],  and  eighteen  or 
twenty  lines  long.  The  Hepatic  Duct  joins,  at  a very 
acute  angle,  with  the  Cystic  Duct,  which  is  somewhat 
smaller  and  shorter,  and  the  two  form  the  Ductus  Com- 
munis Choledochus.  The  biliary  canals  thus  formed, 
are  situated  in  the  right  side  of  the  Hepato  gastric,  or 
lesser  Omentum,  in  what  is  commonly  called  the  Cap- 
sule of  Glisson.  The  Ductus  Communis  being  three 
inehes,  or  three  and  a half  long,  is  to  the  right  of  the 
Vena  Portarum  and  the  Hepatic  artery;  descends  be- 
hind the  pancreas  and  the  upper  part  of  the  duodenum; 
and  passes  obliquely  between  the  coats  of  this  intes- 
tine, for  the  distance  of  an  inch,  its  orifice  being,  as 
mentioned,  at  the  back  of  the  second  turn  of  the  intes- 
tine. 

The  Biliary  ducts  have  two  coats.  The  external  is 
a lamellated  fibrous  membrane,  highly  extensible,  and 
having  many  blood-vessels.  The  internal  is  of  the 
same  character  with  that  of  the  gall-bladder.  In  the 
cystic  canal,  and  towards  the  lower  part  of  the  Ductus 
Communis,  are  several  longitudinal  folds. 

Of  the  Spleen,  ( Lien.  Splen.J 

This  organ,  as  mentioned,  is  situated  deeply  in  the 
left  hypochondriac  region,  in  the  concamty  of  the 
Diaphragm,  at  the  left  extremity  of  the  stomach,  and 


CONTENTS  OF  THE  ABDOMEN. 


243 


above  the  Colon.  Its  form  approaches  to  the  longitu- 
dinal section  of  an  oval,  being  commonly  four  and  a half 
inches  long,  and  two  and  a half  wide.  But  there  is  no 
viscus  in  which  more  frequent  varieties  of  magnitude 
occur.  I have  seen  it  extending  almost  to  the  Ilium, 
and  but  little  smaller  than  the  liver;  and  again,  not  by 
any  means  the  length  just  mentioned  as  a mediuni  size. 
Its  transitions  of  magnitude  are  frequent  and  rapid  in 
the  same  individual,  depending  on  the  stage  of  diges- 
tion, upon  sickness,  and  probably  on  mental  sensations. 
Several  spleens  sometimes  exist  in  the  same  person. 
In  such  cases  the  supernumerary  ones  are,  for  the  most 
part,  very  small. 

The  Spleen  has  a partial  division  lengthwise,  by  a 
fossa,  where  the  blood-vessels  are  connected  with  it. 
Its  circumference  is  sometimes  notched.  Its  colour 
varies  from  a deep  blue,  which  it  is  in  early  life,  to  a 
very  dark  brown.  It  is  fixed  by  three  processes  .of 
peritoneum,  the  names  of  which  indicate  their  attach- 
ments; the  Gastro-splenic,  the  Splenico-phrenic,  and 
the  Splenico-colic  ligaments. 

The  external  coat  of  the  spleen  is  obtained  from  the 
peritoneum,  being  a continuation  of  the  ligaments  just 
mentioned.  The  internal  coat  is  a greyish,  compact, 
extensible,  elastic  membrane,  in  close  adherence  with 
the  external;  it  sends  in  processes  to  accompany  the 
blood-vessels;  and  moreover  from  its  internal  face  there 
proceeds  a multitude  of  lamellae  and  of  fibres,  dividing 
its  cavity  into  cells.  ( Wistar  Museum. ) It  seems  to 


244  OF  THE  TRUNK. 

be  intended  to  sustain  the  natural  shape  of  the  spleen^ 
and  to  support  its  peculiar  structure. 

The  spleen  is  remarkably  well  furnished  with  blood- 
vessels. It  derives  a large  artery  from  the  coeliac, 
distinguished  by  its  tortuous  course,  and  by  the 
branches  which  it  furnishes  to  the  stomach  and  pancreas. 
It  divides  into  several  trunks  just  before  it  enters  the 
spleen.  The  veins  come  out  by  an  equal  number  of 
trunks,  unite  into  one  trunk,  and  attend  the  artery 
along  the  upper  edge  of  the  pancreas;  it  joins  the  Vena 
Portarum. 

In  the  body  of  the  spleen  are  found  many  gi’eyish, 
soft,  semi-transparent  gelatinous  corpuscles,  from  an 
almost  imperceptible  magnitude  to  a line  or  more  in 
diameter.  By  Malpighi,  they  were  considered  glan- 
dular; and  by  Ruysch,  as  convoluted  vessels.  The  mass 
of  the  spleen,  upon  a superficial  examination,  seems  to 
consist  in  a bloody  dark  brown  pulp,  contained  in  the 
numerous  cells  of  the  internal  coat.  On  this  cellular  struc- 
ture, the  vessels  pass.  M.  Assolont  considers  that  blood, 
besides  existing  in  the  arteries  and  veins,  is  placed  in  a 
state  of  particular  combination,  and  of  intimate  union 
with  the  other  organic  elements  of  the  viscus,  and  with 
a large  quantity  of  albumen ; that  this  peculiar  combi  - 
nation  of  the  blood  forms  the  dark  grumous  fluid  just 
mentioned,  which  may  be  easily  seen  by  scraping  the 
spleen  with  the  handle  of  a scalpel.  Of  the  latter, 
there  can  be  no  doubt;  but  a question  arises  whether  it 
is  contained  in  the  cells  I have  just  spoken  of,  or  in  the 


CONTENTS  OF  THE  ABDOMEN.  245 

extremities  of  the  vessels.  Slight  examination  is  in 
favour  of  the  former,  but  M.  Marjolin  denies  it,  on  the 
following  gi’ounds:  That  injections,  cautiously  made, 
pass  immediately  from  the  arteries  into  the  veins  j and 
that  when  the  spleen,  successfully  injected,  is  frozen, 
qne  can  see  no  ice  in  the  interstices  of  the  vessels, 
while  the  capillary  ramifications  of  the  vessels  disten- 
ded hy  the  injected  fluid,  are  distinctly  seen.  The 
probability  then  is,  that  the  peculiar  structure  of  the 
spleen  is  formed  essentially,  of  arterial  and  venous 
capillary  vessels,  with  very  delicate  and  extensible 
coats,  and  that  they  communicate  with  each  other, 
without  the  intermedium  of  any  cell;  and  that  the  ex- 
treme tenuity  of  these  vessels,  and  their  extensibility 
in  every  direction,  are  sufficient  to  explain  the  aug- 
mentation of  volume  which  the  spleen  affords,  under 
certain  circumstances,  and  the  promptitude  with  which 
it  diminishes  under  others. 

Of  the  Pancreas,  {Pancreas.) 

This  is  an  oblong  conglomerate  gland,  extending 
across  the  spine,  and  fixed  in  the  back  and  lower  part 
of  the  epigastric  region.  It  is  connected  to  the  spleen 
on  the  left,  to  the  duodenum  on  the  right,  is  behind 
the  stomach  and  between  the  laminae  of  the  transverse 
mesocolon. 

The  Pancreas  is  of  a light  grey  colour.  It  is  about 
seven  inches  long  and  two  wide;  and  would  represent 


OF  THE  TRraK. 


r24b 

tolerably  a parallellogram,  if  at  its  right  extremity,  it 
were  not  swollen  out  into  a head,  to  which  Winslow 
gave  the  name  of  Small  Pancreas.  It  has  two  faces, 
two  edges,  and  two  extremities.  The  anterior  face 
is  turned  obliquely  upwards  and  corresponds  with  the 
superior  lamina  of  the  mesocolon.  The  posterior  face 
is  obliquely  downwards,  has  a long  fossa  in  its  upper 
part  for  the  splenic  vessels,  and  is  in  contact  witli  the 
aorta,  vena  cava  ascendens,  the  superior  mesenteric 
vessels,  and  several  nerves. 

The  pancreas  has  no  peritoneal  coat,  excepting  the 
mesocolon,  neither  has  it  a proper  tunic,  unless  one 
should  consider  as  such  the  lamina  of  condensed  cellu- 
lar membrane  which  envelopes  it,  and  which  sends 
in  processes  between  its  lobules. 

The  structure  of  the  pancreas  strongly  resembles  that 
of  the  salivary  glands  and  consists  of  granuli,  united 
into  lobules,  which  form  lobes  whose  intei*stices  arc 
occupied  with  numerous  vessels.  The  excretory  duct 
of  the  gland  arises  from  these  granulations,  by  ver)' 
fine  radicles  which,  uniting,  form  larger  cylindei’s  in- 
clining from  left  to  right.  These  latter  empty  succes- 
sively into  a long  tube,  the  Ductus  Wirsungii,  going 
the  whole  length  of  the  gland  and  situated  near  tlie 
very  centre  of  its  substance ; it  is  small  at  the  splenic 
extremity,  but  gradually  increases  till  it  becomes  as 
large  as  a crow’s  quill  at  the  other  end.  It  is  there 
joined  by  the  duct  of  the  lesser  pancreas,  and  in  a short 
course  afterwards  empties  into  the  ductus  communi" 


CONTENTS  OF  THE  ABDOMEN.  247 


choledochus,  or  runs  at  its  side  and  makes  a distinct 
opening  into  the  duodenum  at  the  posterior  part  of  its 
second  curvature. 

The  arteries  of  the  pancreas  are  principally  de- 
rived from  tlie  splenic.  The  veins  empty  into  the 
splenic. 

Of  the  Kidneys,  {Renes,) 

To  get  a good  view  of  the  kidneys,  the  other  abdomi- 
nal viscera  should  be  removed,  or  at  least  the  intes- 
tines. 

The  Kidneys  are  two  glandular  bodies  for  the  secre- 
tion of  urine,  fixed  one  on  each  side  of  the  spine.  They 
are  in  the  back  part  of  the  lumbar  regions  in  a space 
extending  from  the  upper  part  of  the  eleventh  dorsal 
vertebra  to  the  lower  part  of  the  second  lumbar, 
though  the  right,  in  consequence  of  the  pressure  of 
the  liver  from  above,  is  lower  down  than  the  left. 
They  are  deposited  in  a large  parcel  of  fat  on  the  up- 
per part  _of  the  great  psose,  the  quadrat!  lumborum 
muscles,  and  on  the  lower  part  of  the  great  dia- 
phragm. 

The  shape  of  the  kidney  is  a compressed  ovoid  ex^ 
cavated  on  one  side  like  a bean.  The  broad  end  of  the 
ovoid  is  above,  and  the  excavation  presents  obliqudy 
forwards  and  inwards.  The  latter  has  a deep  fissure 
in  it  for  the  passage  of  the  blood-vessels  and  excretory 
duct.  The  kidney  is  hard  and  solid ; its  colour  is  brown . 


248 


OF  THE  TRUNK. 


The  kidney  has  not  a peritoneal  coat^  but  it  has  a 
proper  capsule,  which  completely  envelopes  it  and 
penetrates  into  its  fissure.  The  capsule  is  there  per- 
forated with  many  foramina  for  transmitting  the  blood- 
vessels. This  membrane  is  fibrous,  semi-transparent,  and 
somewhat  elastic ; it  is  easily  peeled  from  the  surface 
of  the  kidney,  and  in  doing  so  we  see  that  it  adiieres 
by  a very  delicate  cellular  and  fibrous  tissue  and  by 
some  small  vessels.  The  kidney  being  originally  form- 
ed in  lobes  which  subsequently  unite,  the  vestige  of 
this  union  is  frequently  preserved. 

The  kidney  being  laid  open  longitudinally,  we  shall 
obtain  an  idea  of  its  internal  arrangement.  It  is  seen 
obviously  to  consist  of  two  parts  of  different  appear- 
ance; the  external;  which,  from  its. position,  is  called 
Cortical;  and  the  Internal  or  Tubular. 

In  regard  to  the  structure  of  the  kidney,  it  receives 
from  the  aorta,  at  right  angles,  a large  artery,  the 
Emulgent,  which  divides  into  several  branches  as  it  ap- 
proaches the  fissure  ; these  terminate  by  penetrating  to 
all  parts  of  the  gland  in  a crowd  of  arterioles,  so  that 
when  they  are  injected  with  wax  and  corroded,  the 
figure  of  the  gland  is  preserved.  Some  of  these  mi- 
nute arterial  branches  terminate  in  corresponding  veins, 
others  in  the  parenchymatous  structure  of  the  organ, 
and  others  in  the  excretory  branches. 

The  Cortical  part  is  the  most  vascular ; it  is,  at  an 
average,  about  two  lines  in  depth,  and  forms  the  peri- 
phery of  the  gland,  but  different  portions  of  it  project 


CONTENTS  OF  THE  ABDOMEN. 


249 


and  form  partial  partitions  between  the  tubular  sections. 
It  tears  with  facility,  with  a granulated  edge  or  surface^ 
and  its  colour  is  a dark  or  reddish  brown.  When  view- 
ed with  a microscope  the  granulations  are  distinctly 
seen  of  extreme  minuteness,  and  formed  by  the  capil- 
lary extremities  of  arteries  and  veins.  I have  more 
than  once  injected  these  granulations  from  the  arteries, 
and  observed  the  fluid  coming  through  the  ureter  and 
the  emulgent  vein. 

The  second  or  Tubular  portion  of  the  kidneys,  to  the 
naked  eye,  consists  of  conoidal  fasciculi  of  fibres  pre- 
senting their  bases  to  the  periphery  of  the  organ,  and 
their  apices  towards  its  centre.  These  cones  are  from 
twelve  to  eighteen  in  number,  and  as  mentioned,  are 
partially  separated  from  each  other  by  processes  from 
the  cortical  part ; they  are  dense,  of  a lighter  brown, 
and  tear  with  facility  in  the  course  of  the  fibres.  Each 
cone  is  formed  by  a great  number  of  very  fine  canals 
converging  close  to  each  other  near  the  apex,  and 
continuous  at  the  other  end  with  the  vessels  of 
the  cortical  part.  They  appear  only  to  give  passage 
to  the  urine,  as  cases  have  occurred,  in  which  they  were 
entirely  removed  by  suppuration  and  ulceration.  (See 
Wistar  Museum.)  The  technical  name  for  these  canals 
is  Tubuli  Uriniferi.  The  terminations  of  the  cones 
are  called  Papillse,  and  an  attempt  has  been  made  to 
establish  for  them  some  peculiarity  of  organization  | 
but  tliat  idea  is  now  abandoned,  and  they  are  generally 
admitted  to  be  the  same  with  the  other  portions  of  the 


OF  THE  TRUNK. 


yoO 

tubular  part.  They  have  many  orifices  in  them  wiiick 
are  the  terminations  of  the  tubes,  and  from  which  urine 
in  most  subjects  can  be  readily  squeezed. 

Of  the  Excretory  Ducts  of  the  Kidnies. 

The  excretory  duct  of  the  kidney  begins  in  its  een 
tre  by  a dilatation  called  Pelvis,  branching  into  several 
funnel  shaped  tubes  named  Infundibula.  Generally 
three  or  four  of  the  latter  discharge  by  their  little  ends 
into  a common  tube,  and  the  union  of  three  or  four  of 
the  latter,  as  the  case  may  be,  constitutes  the  pelvis 
of  the  kidney.  Each  papilla  has  its  appropriate  infun- 
dibulum ; but  sometimes  there  are  two  of  the  former, 
to  but  one  of  the  latter;  there  are  besides  many  other 
modifications  in  the  collateral  arrangement  of  the  gland, 
which  could  not  be  introduced  into  an  abbreviation  like 
the  present. 

The  excretory  duct  of  the  kidney  has  two  coats,  the 
external  of  which  is  fibrous  and  the  internal  mucous. 
The  latter  is  said  to  be  continued  over  the  papillae,  and 
may  probably  enter  into  the  tubuli  uriniferi.  It  enjoys 
a great  degree  of  extensibility  and  contractility  of  tis- 
sue, and  its  sensibility  not  perceptible  in  health,  is  ex- 
quisite in  disease. 

The  Pelvis  of  the  kidney  is  continued  into  the  ureter,  a 
canal  about  the  size  of  a writing-quill,  and  which  is  in 
contact  behind  with  the  psoas  magnus  muscle,  and  the 
iliac  and  hypogastric  vessels,  crosses  the  vas  deferens 


CONTENTS  OF  THE  ABDOMEN.  25] 

at  the  back  part  of  the  bladder,  and  passes  obliquely 
through  the  coats  of  the  latter,  to  end  in  an  orifice  a 
little  behind  that  of  the  Urethra. 

The  emula:ent  veins  are  uarallel  with  the  arteries,  and 
terminate  in  the  vena  cava  ascendens. 

Of  the  Renal  Capsules,  {Capsulse  Renales.) 

They  are  two  little  triangular  pyramidal  bodies, 
one  for  each  kidney  and  placed  at  its  superior  part : they 
are  of  a yellowish  brown  colour  somewhat  tinged  with 
red,  and  being  connected  with  some  process  of  foetal 
existence,  are  much  larger  then  than  in  the  adult; 
their  structure  also  seems  to  be  much  clianged  in  the  lat- 
ter. From  being  placed  precisely  on  the  upper  extre- 
mity of  the  kidney  they  have  the  lower  surface  which 
touches  it  of  a corresponding  concavity. 

On  the  exterior  of  this  body  is  a proper  coat  formed 
of  lamellated  and  condensed  cellular  tissue,  which  fur- 
nishes from  its  internal  surface  many  prolongations  di- 
viding the  gland  into  lobes.  These  lobes  are  di\dsible 
into  lobules,  which  again  consist  of  a granulated  struc- 
ture that  seems  susceptible  of  other  divisions.  These 
granulations  are  not  firm  and  resisting. 

In  the  centre  of  the  Capsula  Renalis,  sometimes 
there  is  a triangular  cavity  which  may  be  demonstrated 
by  thrusting  a tube  into  it,  and  inflating,  or  by  an  in- 
cision. In  the  foetus  this  cavity  contains  a reddish 
Auscid  fluid  coagulable  bv  alcohol ; in  children  it  be- 


252 


OF  THE  TRUNK. 


comes  yellow : in  adults  it  is  dark  brown,  and  in  old 
people  it  is  either  wanting  or  in  a remarkably  small 
quantity. 

The  arteries  of  these  bodies  come  from  the  emul- 
gents,  the  phrenics  and  the  aorta.  The  veins  termi- 
nate on  the  right  side  in  the  cava,  and  on  the  left  in  the 
emulgent. 


Section  V. 

The  Diaphragm,  {Diaphragma,') 

Is  a complete,  though  moveable  septum,  placed  be- 
tween the  thoracic  and  abdominal  cavities;  it  is  ex- 
tremely concave  below  and  convex  above,  the  concavity 
being  occupied  by  several  of  the  abdominal  viscera. 
To  view  it  properly,  all  the  abdominal  viscera  should 
be  removed,  a large  billet  of  wood  placed  under  the  loins 
of  the  subject,  and  the  peritoneum  carefully  dissected 
olf.  It  is  particularly  necessary  to  attend  to  the  latter 
direction  in  order  to  get  a good  view  of  the  varied 
structure  of  this  important  organ,  and  the  dissector, 
while  performing  it,  is  continually  liable  to  the  accident 
of  a puncture  being  made  through  it  into  the  thorax ; 
in  which  case  the  diaphragm  loses  its  concavity,  and 


DIAPHRAGM. 


253 


becoming  flabby  and  displaced,  the  value  and  beauty 
of  the  display  are  much  impaired,- 

The  dissection  being  properly  achieved,  exhibits  a 
broad  concave  muscle  connected  with  the  inferior 
margin  of  the  thorax  on  all  sides,  and  having  for  its 
centre  a silvery  tendon  resembling  in  its  outline  the 
heart  of  a playing  card.  This  cordiform  tendon  oc- 
cupies a considerable  part  of  the  extent  of  the  dia- 
phragm, having  its  apex  next  to  the  sternum  and  its 
notch  towards  the  spine ; the  muscular  part  of  the  dia- 
phragm is  inserted  all  around  its  circumference.  The 
cordiform  tendon  is  nearly  horizontal  in  the  erect  pos- 
ture, its  elevation  being  on  a line  with  the  lowest  end 
of  the  second  bone  of  the  sternum.  On  each  side  of 
this  tendon  the  muscular  fibres  rise  so  high  upwards 
before  they  join  it,  that  they  are  on  a horizontal  level 
with  the  anterior  end  of  the  fourth  rib.  The  fasciculi 
of  muscular  fibres  are,  for  the  most  part,  convergent 
from  the  circumference  of  the  thorax,  and  are  easily 
separated  from  each  other. 

In  the  diaphragm  are  three  remarkable  foramina. 
The  first  is  in  the  back  of  the  muscle  between  the  spine 
and  the  notch  of  the  cordiform  tendon,  a little  to  the 
left.  It  gives  passage  to  the  oesophagus  and  the  par 
vagum  as  connected  with  it,  and  is  rather  a fissure  or  a 
long  elliptical  foramen  made  by  the  separation  and 
reunion  of  the  muscular  fibres;  for  above  and  below  at 
each  end  of  the  ellipsis  these  fibres  decussate  each  other 
in  columns.  To  the  right  of  this  foramen  aiid  a little 


254 


OF  THE  TRUNK. 


above  its  horizontal  level  in  the  back  part  of  the  cordi' 
form  tendon,  is  a very  large  and  patulous  foramen  for 
the  ascending  vena  cava.  It  is  between  an  irregular 
quadrilateral  figure  and  a circle;  its  edges  are  composed 
of  fasciculi  of  tendon  rounded  off,  and  are  not  suscep- 
tible of  displacement,  or  of  alteration  in  their  relative 
position  to  each  other,  by  which  means  is  obviated  any 
impediment  which  might  arise  from  a different  arrange 
ment,  to  the  course  of  the  blood  in  the  ascending  cava. 
Almost  in  a vertical  line  below,  but  about  three  inches 
from  the  foramen  for  the  oesophagus,  is  the  third  hole 
in  the  diaphragm,  which  affords  passage  to  the  aorta. 
It  is  just  in  front  of  the  bodies  of  the  three  upper  lum- 
bar vertebrae,  and  is  a much  longer  elliptical  hole  than 
the  oesophageal;  its  lowest  extremity  or  pole  is  consti- 
tuted by  the  tendinous  crura  of  the  diaphragm,  and  its 
upper  by  a decussation  of  muscular  fasciculi  arising 
from  them.  Through  it,  besides  the  aorta,  pass  the 
Thoracic  Duct,  and  the  Great  Splanchnic  Nerve  from 
each  side. 

In  the  horizontal  position  of  either  the  dead  or  tlie 
living  body,  the  right  side  of  the  diaphragm  ascends 
higher  in  the  thorax  than  the  left,  but  the  weight  of 
the  liver  makes  it,  in  the  vertical  posture,  descend 
lower  than  the  other. 

Thus  circumstanced,  the  Diaphragm  arises  fleshy, 
from  the  internal  face  of  the  upper  edge  of  the  Xi- 
phoid Cartilage,  from  the  internal  face  of  the  cartilages 
of  the  seventh  true,  and  of  the  succeeding  false  ribs. 


DIAPHRAGM. 


255 


on  each  side.  That  is,  from  tlie  cartilages  of  the  eightli 
and  ninth,  from  the  osseous  extremities  of  the  tenth  and 
eleventh,  and  from  both  the  osseous  and  cartilaginous 
termination  of  the  twelfth  rib.  As  the  line  described 
includes  almost  the  whole  of  a circle,  and  the  fibres  all 
converge  to  the  cordiform  tendon,  they,  of  course,  will 
pass  in  different  radiated  directions,  and  be  of  different 
lengths,  which  it  is  unnecessary  to  specify.  Between 
the  sternal  and  costal  portions,  on  each  side,  there  is  a 
triangular  fissure  filled  with  fatty  cellular  tissue,  which 
sometimes  leaves  an  opening  for  Hernia.  I have  seen 
a case  of  this  kind,  in  which  the  transverse  part  of  the 
Colon  was  the  subject  of  protrusion  into  the  Thorax; 
It  is  probable  that  the  great  displacement  of  the  abdo- 
minal viscera,  into  the  thorax  of  adults  or  children,  may 
have  had  a congenital  origin  in  this  very  fissure,  and 
is  subsequently,  when  the  parts  are  modified  to  this 
unnatural  situation,  set  down  as  a Lusus  Naturae.  The 
part  described,  is  called  the  greater  muscle  of  the  Dia- 
phragm. 

Besides  these  origins,  the , Diaphragm  has  several 
from  the  vertebras  of  the  loins,  called  its  crura,  there 
being  four,  on  each  side  of  the  foramen  for  the  aorta. 
The  first  pair,  entirely  tendinous,  comes  from  the  front 
of  the  body  of  the  third  vertebra  of  the  loins,  and  is 
prevented  from  being  very  distinct  in  its  origin,  in 
consequence  of  running  into  the  ligament  in  front  of 
the  bodies  of  all  the  vertebrae.  The  second  pair  of 
heads  is  on  the  outside  of  the  first,  and  arises  tendinous 


236 


OF  THE  TRUNK. 


from  the  Intervertebral  ligament,  between  the  second 
and  third  vertebrae.  The  third  pair  of  heads  arises 
tendinous  from  the  upper  part  of  the  lateral  margins 
of  the  second  lumbar  vertebra.  And  the  fourth  pair  of 
heads  comes  also  tendinous  from  the  fore  part  of  the 
roots  of  the  transverse  processes  of  the  second  lumbar 
vertebra.  These  tendinous  heads  terminate  in  what  is 
called  the  Lesser  muscle  of  the  Diaphragm,  which  is 
inserted  into  the  notch  of  the  cordiform  tendon.  It 
will  now  be  understood  that  the  aorta  passes  between 
the  heads  of  the  lesser  muscle,  and  that  the  oesophagus 
has  a hole  in  the  upper  part  of  its  belly.  * 

The  origin  of  the  Diaphragm  is  completed  between 
its  greater  and  lesser  muscles,  by  a tense  ligament, 
called  Ligamentum  Arcuatum,  which  passes  from  the 
root  of  the  transverse  process  of  the  first  lumbar  ver- 
tebra to  the  inferior  part  of  the  middle  of  the  twelfth 
rib;  with  the  upper  edge  of  this  ligament  the  Dia- 
phragm is  connected;  and  with  the  lower,  the  psoas 
magnus  muscle.  At  the  margin  of  the  other  ribs,  the 
diaphragm  is  connected  with  the  transversalis  abdo- 
minis. 

The  action  of  this  muscle,  in  assisting  respiration, 
is  very  obvious ; its  fibres  passing  in  a curved  line  with 

This  origin  of  the  lesser  muscle  of  the  Diapliragm  is  given 
by  Albiniis,  but  it  is  difficult  to  make  out  fairly,  and  for  the 
most  part  it  would  be  much  better  to  say  that  it  arises  tendinous, 
from  the  first,  second,  and  third  vertebrae.  The  heads  arc 
occasionally  much  sumher  on  one  side  than  the  otlier. 


PSOAS  MAGNUS. 


257 


their  convexity,  towards  the  thorax,  from  the  bony 
margin  of  the  thorax  to  the  cordiform  tendon,  and  hav- 
ing a tendency  to  become  straight  by  contracting, 
will  descend,  and  thereby  enlarge  the  thorax.  It  is 
not  certain  that  the  cordiform  tendon  descends,  its  con- 
nexions being  too  strong  and  numerous  to  admit  of 
much  motion.  In  expiration,  the  relaxation  of  the 
Diaphragm,  with  the  contraction  of  the  abdominal 
muscles,  restore  the  former  to  its  first  state.  In  vomit- 
ing, the  Diaphragm  and  abdominal  muscles  concur  to 
expel  the  contents  of  the  stomach. 

The  Psoas  Magnus  muscle  arises,  fleshy,  from  the 
side  of  the  bodies  of  the  last  dorsal  and  of  the  four  up- 
per lumbar  vertebrae,  and  from  the  transverse  pro- 
cesses of  all  the  lumbar  vertebrae.  It  forms  an  oblong 
fleshy  cushion  on  the  side  of  the  lumbar  vertebrae,  and, 
constituting  the  lateral  boundary  of  the  inlet  to  the  pel- 
vis, it  passes  out  of  the  pelvis,  under  Poupart’s  ligament 
about  its  middle. 

It  is  inserted,  tendinous,  into  the  trochanter  minor 
df  the  os  femoris,  and  fleshy  for  an  inch  below  it. 

It  bends  the  body  forwards,  or  draws  the  thigh  up- 
wards. 

The  Psoas  Parvus,  arises,  fleshy,  from  the  conti- 
guous edges  of  the  last  dorsal  andof  the  first  lumbar  verte- 
bra at  their  sides,  and  from  the  intervertebral  ligament. 
It  is  at  the  anterior  and  internal  edge  of  the  psoas  mag- 

K k 


258 


OF  THE  TRUNK. 


nus  ; has  a short  belly,  and  a long  tendon  by  which  it 
is  inserted  into  the  linea  innominata,  about  half-way  be- 
tween the  spine  of  the  pubes  and  the  junction  of  this 
bone  with  the  ilium.  The  tendon,  besides,  is  expand- 
ed into  the  fascia  iliaca. 

Its  use  seems  to  be,  to  draw  upwards  the  sheath  of 
the  femoral  vessels  which  is  derived  from  the  fascia 
iliaca,  and  consequently  to  draw  upwards  the  vessels 
themselves,  which  probably  diminishes  the  liability  to 
injury  from  their  too  great  or  sudden  flexion.  This 
muscle  is  sometimes  wanting. 

The  Iliacus  Internus  occupies  the  concavity  of 
the  ilium,  being  on  the  outside  of  the  psoas  magnus. 
It  arises,  fleshy,  from  the  transverse  process  of  the  last 
lumbar  vertebra,  from  the  inner  margin  of  the  crista 
of  the  ilium,  and  from  its  whole  concavity ; also  from 
the  anterior  edge  of  the  concavity  of  the  ilium  at  and 
above  the  anterior  inferior  spinous  process,  and  from 
that  part  of  the  capsule  of  the  hip  joint  near  this  process. 

This  muscle  terminates  in  the  tendon  of  the  psoas 
magnus  just  above  the  insertion  into  the  trochanter 
minor. 

It  has  the  same  action  with  the  psoas  magnus. 

The  Quadrates  Lumborum  is  an  oblong  muscle 
passing  from  the  back  part  of  the  spine  of  the  ilium,  by 
a tendinous  and  fleshy  origin  of  two  inches  in  length. 
It  lies  at  the  side  of  the  lumbar  vertebrae,  into  all  the 


QUADRATUS  LUMBORUM. 


259 


transverse  processes  of  which  it  is  inserted  by  short 
tendinous  slips.  It  is  also  inserted  into  the  lower  edge 
of  the  last  rib  just  by  its  head,  and  into  the  transverse 
process  of  the  last  vertebra  of  the  back. 

It  bends  the  loins  to  one  side,  and  will  draw  down 
the  last  rib.  This  muscle  is  covered  posteriorly,  by  the 
tendinous  origin  of  the  transversalis  abdominis  muscle, 
which  separates  it  from  the  sacro  lumbalis  and  longis- 
simus  dorsi. 


PART  II. 


CHAPTER  III. 

Of  the  Male  Pelvis. 

I HAVE  chosen  to  give  this  a distinct  chapter  not 
only  on  account  of  its  importance,  but  because  the  dis- 
sections which  are  performed  on  it  have  but  little  con- 
nexion with  the  parts  just  described,  are  performed  in 
very  different  postures  of  the  subject  from  the  preceed- 
ing,  and  have  in  them  an  intrinsic  difficulty  requiring 
them  to  be  made  in  several  ways  in  order  to  exhibit 
well  the  relative  position  and  anatomy  of  the  parts. 

I conceive  that  the  first  step  of  the  student,  after  a 
short  examination  in  situ  of  the  contents  of  the  pelvis, 
should  be  to  detach  the  penis  from  its  bony  connexions 
and  to  remove  it,  with  the  bladder  and  rectum,  from 
the  pelvis.  Then  to  make  a fair  and  clean  dissection 
of  these  organs  by  detaching  the  surrounding  fat,  cel- 
lular membrane,  and  muscles.  This  dissection  is  best 
made  with  the  scissors,  and  its  utility  is  in  proportion 
to  its  cleanness ; the  latter  is  much  assisted  by  inflating 
the  bladder  and  by  stuffing  the  rectum.  The  scrotum 
may  be  separated  and  laid  aside  for  future  examina- 
tion. 


MALE  PELVIS. 


261 


Section  I. 

Of  the  Viscei'a  of  the  Male  Pelvis. 

The  Peetum,  being  the  termination  of  the  colon,  be- 
gins at  the  left  sacro-iliac  symphysis;  from  thence 
it  passes  down  obliquely  towards  the  middle  of  the  sa- 
crum about  one -half  of  its  length ; its  course  afterwards, 
is  directly  downwards  before  the  sacrum  and  os  coc- 
cygis  till  it  terminates  in  the  anus;  its  orifice  there  points 
backwards  and  dowmwards.  It  is  cylindrical  till  just 
before  its  termination,  it  then  dilates  into  a pouch  which 
is  spread  on  each  side  of  the  prostate,  and  is  apt  to  be 
cut  in  lithotomy. 

The  inferior  third  of  the  rectum  is  destitute  of  pe- 
ritoneum, its  anterior  face  is  in  contact  with  the  lower 
fundus  of  the  bladder,  the  vesiculag  serainales,  and  the 
prostate  gland.  Posteriorly  and  above,  it  is  confin- 
ed to  the  sacrum  by  the  mesorectum,  which  conducts 
its  nerves  and  blood-vessels.  The  dip  of  the  peri- 
toneum, between  the  vesiculae  seminales  so  as  almost 
to  touch  the  base  of  the  prostate  gland  should  be  re- 
marked. 

The  muscular  structure  of  this  gut  is  remarkably 
strong,  consisting,  externally,  of  vertical  and  parallel 
fasciculi  of  fibres  close  together,  and  internally  of  cir- 


262 


OF  THE  TRUNK. 


cular  fibres  which  form  a thick  and  continued  plane, 
particularly  on  a level  with  the  lower  fundus  of  the 
bladder.  Just  below  the  pouch  of  the  reetum  these 
circular  fibres  form  the  Internal  Sphincter  Muscle. 
The  mucous  membrane  of  the  gut  is  smooth  above,  but 
at  the  lower  part  it  is  thrown  into  several  longitudinal 
folds,  called  the  Columns  of  the  Rectum.  The  villosi- 
ties  of  this  surface  are  distinguishable,  as  well  as  its 
mucous  lacunae  which  are  numerous.  The  anus  is 
. thrown  into  radiated  folds  from  the  influence  of  the 
sphincter  ani. 


The  Bladder^  (Vesica  Urinaria,)  is  fixed  just  behind 
the  symphysis  of  the  pubes  and  when  pressed  upon  by 
the  neighbouring  viscera,  is  somewhat  flattened  before 
and  behind;  but  removed  from  the  body  and  distended, 
it  resembles  an  elongated  sphere,  of  which  the  greatest 
diameter  is  vertical  in  regard  to  the  linea  ilio  pectinea. 
The  technical  name  for  each  end  of  the  sphere  is  F un- 
dus,  distinguished  by  the  terms  upper  and  lower,  the 
lower  being  somewhat  the  more  obtuse.  From  the 
upper  end  proceeds  to  the  navel  a long  conical  liga- 
ment, the  Urachus.  By  putting  the  anterior  parietes  of 
the  abdomen  on  the  stretch  we  shall  see  starting  out 
and  protruding  the  peritoneum  into  a semilunar  dupli- 
cature  on  each  side  of  the  urachus,  the  remains  of  the 
umbilical  arteries  of  the  foetus  which  now  are  called  the 
Round  Ligaments  of  the  bladder,  though  they  have  but 
little  or  no  influence  on  it.  At  the  anterior  part  of  the 


MAI.E  PET.VIS. 


263 


lower  fundus,  the  bladder  is  somewhat  elongated  into  a 
process  called  its  Neck,  resembling  a truncated  cone, 
and  being  the  commencement  of  the  urethra. 

The  bladder  consists  of  four  tunics;  the  Peritoneal, 
Muscular,  Cellular,  and  Mucous. 

The  Peritoneal  is  a very  incomplete  coat  placed 
upon  the  upper  and  posterior  parts  of  the  bladder,  and 
passing  from  it  to  the  muscles  of  the  abdomen  before, 
and  to  the  rectum  behind.  It  is  connected  to  the 
muscular  coat  by  very  loose  cellular  membrane,  which 
prevents  it  from  participating  in  any  considerable  dis- 
tentions of  the  organ,  and  permits  it  to  leave  the  ante- 
rior face  of  the  bladder,  so  that  its  reflection  to  the 
recti  muscles  in  these  cases,  is  placed  much  above  the 
pubes.  Tapping  is  performed  here,  as  well  as  the  high 
operation  for  the  stone. 

The  Muscular  coat  consists  of  flattened  fasciculi 
of  white  fibres  passing  in  very  varied  directions,  and 
separated  to  some  distance  from  each  other.  Many  of 
them  arise  from  the  neck  of  the  bladder  and  pass  before 
and  behind  upwards  towards  the  urachus,  where  they 
end;  others,  arising  laterally  from  the  same  place,  pass 
up  in  a corresponding  course  and  also  terminate  at  the 
urachus.  There  are  many  transverse  and  oblique 
fibres  uniting  these  together,  but  still  leaving  interstices 
through  which  the  internal  coat  occasionally  protrudes, 
and  thus  forms  cells  in  the  cavity  of  the  bladder. 


264  OF  .THE  TRUNK. 

There  is  an  accumulation  of  fibres  about  the  neck  of 
the  bladder  and  the  urachus,  which  gives  an  increased 
thickness  at  these  points. 

The  Cellular  coat  consists  of  a close,  dense,  lamel- 
lated,  and  fibrous  tissue,  highly  extensible  and  difficult 
to  tear.  It  is  impervious  to  water,  closely  adherent  to 
the  muscular  and  mucous  membranes,  and  pervaded  by 
many  vessels. 

The  Mucous,  or  internal  coat  of  the  bladder,  though 
called  villous,  has  less  of  this  appearance  than  tliat  of 
the  stomach.  It  is  white  with  a slight  tinge  of  red; 
abounds  with  mucous  follicles  which,  in  a state  of  health, 
are  difficult  to  be  discerned;  possesses  great  extensi- 
bility and  but  little  contractility,  from  whence,  when 
the  bladder  is  not  very  full,  it  is  thrown  into  folds  pass 
ing  in  various  directions.  It  offers  several  points  for 
observation.  1.  A triangular  space  between  the  orifice 
of  the  urethra  and  those  of  the  ureters,  (the  Trigone 
Vesicale  of  die  French,)  which  is  elevated  into  a plain 
smooth  surface.  Mr.  Charles  Bell  thinks  the  lateral 
margins  have  muscular  fibres  beneath  intended  to  regu- 
late the  orifices  of  the  ureters.*  2.  The  Uvula 
Vesicse,  a small  pointed  production  terminating  the 
triangle  in  front,  and  formed  by  a projection  of  the 

* My  personal  Investigations  on  this  point  have  not  verified 
the  assertion. 


MALE  PELVIS. 


265 


third  lobe  of  the  prostate  gland  into  the  cavity  of  the 
bladder.  3.  The  orifices  of  the  ureters,  about  an  inch 
behind  the  orifice  of  the  urethra.  4.  The  Inferior 
Fundus,  (bas-fond  of  the  French,)  a depression  of  the 
general  concavity  of  the  bladder  making  it  lower  than 
any  other  part,  placed  between  the  base  of  the  trigone 
and  the  posterior  side  of  the  bladder.  5.  The  Inter- 
nal Orifice  of  the  neck  of  the  bladder,  resembling  some- 
what a crescent,  extending  its  horn  around  the  uvula 
vesicse. 

The  Neck  of  the  Bladder  is  thicker  than  any  other 
part  5 it  is  surrounded  by  cellular  tissue  in  which  a 
great  number  of  veins  is  found,  and  it  penetrates,  in 
front,  the  prostate  gland,  which  has  a continual  tendency 
to  close  it.  The  muscular  fibres  concurring  in  its  forma- 
tion have  not  been  considered,  by  the  greater  number 
of  anatomists,  as  sufficiently  regular  to  form  a distinct 
sphincter  muscle,  but  Mr.  Charles  Bell  differs  from 
them  and  gives  the  following  account  of  it:  Begin 

the  dissection  by  taking  off  the  inner  membrane  of  the 
bladder  from  around  the  orifice  of  the  urethra.  A set 
of  fibres  will  be  discovered  on  the  lower  half  of  the 
orifice  which,  being  carefully  dissected,  will  be  found 
to  run  in  a semicircular  form  round  the  urethra.  These 
fibres  make  a band  of  about  half  an  inch  in  breadth, 
particularly  strong  on  the  lower  part  of  the  opening, 
and,  having  mounted  a little  above  the  orifice  on  each 
side,  they  disperse  a portion  of  their  fibres  in  the  sub- 
stance of  the  bladder.  A smaller  and  somewhat  weaker 

L 1 


266 


OF  THE  TRUNK. 


set  of  fibres  will  be  seen  to  complete  their  course,  sur- 
rounding the  orifice  on  the  upper  part;  to  these  sphinc- 
ter fibres  a bridle  is  joined,  which  comes  from  the  union 
of  the  muscles  of  the  ureters.” 

ProUate  Gland,  {Glandida  Parastata.) 

This  is  a body  about  the  size  and  form  of  a hoi’se 
chestnut,  fixed  on  the  neck  of  the  bladder,  and  pene- 
trated by  tbe  urethra,  which  traverses  it  much  nearer 
its  superior  than  its  inferior  surface.  The  base  of  it  is 
turned  backwards,  and  the  point  forwards;  its  inferior 
surface  rests  upon  the  rectum,  and  its  sides,  in  the  dis- 
tentions of  this  organ  by  fasces,  are  overlapped  by  it. 
The  Prostate  has,  posteriorly,  a notch  in  its  centre, 
which  divides  it  into  two  lateral  lobes,  and  by  raising 
the  Vesiculas  Seminales,  we  shall  see  where  their  ex- 
cretory ducts  penetrate  the  gland,  and  separate  from 
the  body  of  it  the  little  tubercle,  to  which  Sir  Everard 
Home,  has  particularly  called  the  attention  of  the  pro- 
fession, and  considered  as  a Third  Lobe,  it  being  cer- 
tain that  it  is  frequently  the  seat  of  disease  and  tume- 
faction. (See  Wistar  Museum.) 

The  organization  of  this  body  seems  to  consist  in  a 
condensed,  white,  extensible,  though  easily  lacerated 
cellular  tissue,  and  within  it  are  placed  a great  numbei’ 
of  mucous  follicles,  which  form  from  eight  to  twelve 
ducts,  passing  obliquely  forwards,  and  terminating  in 
the  urethra  on  each  side  of  the  urethral  crest  or  Caput 


MALE  PELVIS. 


26? 


Gallinaginis.  The  fluid  secreted  is  thick,  ropy,  white, 
and  semitransparent  in  a healthy  state.  The  Prostate 
is  surrounded  by  a fibrous  capsule,  of  which  more 
hereafter.* 

The  Seminal  Vesicles,  (Vesiculm  Seminales,)  are 
two  convoluted  bodies  of  two  inches  in  length,  one  on 
each  side  of  the  lower  fundus  of  the  bladder,  approach- 
ing each  other  very  nearly  at  the  base  of  the  Prostate, 
but  diverging  much  as  they  recede.  They  are  sepa- 
rated before,  by  the  interposition  of  the  vasa  deferential 
and  being  fixed  between  the  rectum  and  the  bladder, 
they  are  matted  to  the  latter  by  a close  cellular  mem- 
brane, having  many  large  veins  pervading  it. 

When  inflated  and  dried,  they  present  the  semblance 
of  cells,  but  are  in  fact  long  tubes,  which,  by  being 
convoluted,  are  reduced  to  the  apparent  dimensions 
mentioned : there  are  also  several  pouches  on  each  side 
of  this  long  tube  which  increase  the  number  of  cells. 
The  convolutions  are  preserved  by  the  intermediate 
cellular  tissue.  These  bodies  consist  of  two  coats,  an 
external,  which  is,  fibrous  and  cellular ; and  an  internal, 
which  is  mucous,  being  a continuation  of  the  lining 
membrane  of  the  bladder.  They  are  commonly  filled 
by  a drab-coloured  thick  fluid,  supposed  to  be  a 

* An  opinion  prevails  among  the  anatomists  of  Philadelphia, 
that  the  prostate  is  larger  in  the  African  than  in  whites.  Indeed 
this  much  may  be  said  of  all  the  organs  of  generation  in  both 


sexes. 


268 


OF  THE  TRUNK. 


mixture  of  the  semen,  and  of  their  own  proper  sec  re 
tion,  though,  of  this,  Mr.  Hunter  doubted.*  The  ex- 
cretory duct  of  each  vesicle  is  about  a line  and  a half 
long,  when  it  joins  in  the  substance  of  the  prostate 
with  the  vas  deferens  of  the  same  side;  a common 
canal,  (Ductus  Ejaculatorius)  is  thus  formed,  which 
runs  parallel  with  its  fellow,  below  the  urethra. 

The  Ductus  Ejaculatorius,  is  about  eight  or  ten 
lines  long,  and  opens  by  an  oblong  orifice,  at  the  late- 
ral anterior  face  of  the  Caput  Gallinaginis ; it  is  larger 
behind  than  before,  which  gives  it  a conical  shape,  and 
allows  fluids  injected  to  pass  freely  from  the  vas  defe- 
rens to  the  vesicula,  or  the  reverse.  . 

Of  the  Penis,  {^Memhrum  Virile,  Meniula.) 

It  is  a membranous  and  cellular  body  afiixed  to  the 
margin  of  the  pelvis,  at  and  below  the  symphysis  pubis, 
and  appropriated  to  the  passing  of  urine  and  semen. 
It  is  formed  by  the  common  integuments,  by  cellular 
tissue,  by  the  corpus  cavernosum,  and  by  the  corpus 
spongiosum. 

The  skin  covering  the  penis  is  more  thin  and  deli- 
cate than  in  most  other  parts  of  the  body,  and  is  fur- 
nished with  a considerable  number  of  sebaceous  follicles, 
more  particularly  about  the  root  of  the  organ.  It  is 

See  Observations  on  the  Animal  (Economy. 


Mx\LE  PELVIS. 


269 


very  loosely  connected  by  cellular  membrane  to  the 
parts  beneath,  so  that  -it  is  easily  made  to  correspond 
with  all  states  of  the  penis.  At  the  anterior  extremity 
it  is  arranged  into  a duplicature  or  fold,  the  Prepu- 
tium,  which  is  inserted  just  behind  the  glans;  the 
iiiferior  part  of  the  prepuce  is  connected  with  the  ex- 
tremity of  the  glans  by  a process  called  Frsenum. 

The  penis,  besides  arising  from  the  bones  of  the 
pelvis  in  a manner  which  will  be  presently  explained, 
is  fixed  to  the  symphysis  pubis  by  a ligament,  (Liga- 
mentum  Suspensorium,)  which  is  a triangular  fibrous 
body,  flattened  triansversely  and  lost  insensibly  on  the 
fascia  of  the  thigh  covering  the  adductor  muscles.  The 
portion  of  it  which  goes  to  the  penis  arises  in  front  of  the 
symphysis  pubis  and  is  inserted  into  the  dorsum  of  the 
penis  near  its  root ; from  this  insertion  it  is  extended 
laterally  over  the  penis,  and  according  to  Mr.  Colles  con- 
stitutes one  of  its  coverings,  by  going  as  far  as  the  glans. 
Professor  Marjolin  says  that  he  has  seen  on  several 
occasions  muscular  fibres  entering  into  its  composi- 
tion, and  in  that  case  it  draws  the  organ  with  more 
force  towards  the  anterior  parietes  of  the  abdomen.* 

The  Corpus  Cavernosum  of  the  penis,  forms  by 
inuch  the  most  considerable  portion  of  the  whole  organ. 
Externally  it  is  a white  fibrous  membrane  of  a dense 
structure,  enjoying  extensibility  and  an  extreme  de- 
gree of  contractility ; its  fibres  pass  for  the  most  part 

* I have  seen  it  in  one  case,  Febniary  1 1th  1825, 


270 


OF  THE  TRUNK. 


longitudinally,  except  about  the  root,  where  they  arc 
blended  with  the  periosteum  of  the  bone,  and  with  the 
tendons  of  the  muscles.  This  coat  of  the  penis  is  occa- 
sionally called  its  elastic  ligament.  It  arises  by  tw'o 
conical  crura,  one  from  the  internal  face  of  the  crus  of 
each  pubes  and  ischium,  to  wdthin  a little  distance  of 
the  anterior  part  of  the  tuber  ischii.  At  the  lower 
part  of  the  symphysis  pubis  these  crura  join  and  form 
a body,  which,  when  stripped  of  its  connexions,  resem- 
bles two  cylinders  lying  along  side  of  each  other  and 
united ; anteriorly  they  terminate  in  common  by  a trun- 
cated cone  covered  obliquely  by  the  glans.  At  the  pos- 
terior part  of  the  corpus  cavernosura,  in  its  centre, 
there  is  a tolerably  complete  septum  of  the  same  kind 
of  substance,  separating  its  tw  o halves  from  each  other, 
but  anteriorly  this  septum  is  imperfect,  having  an 
arrangement  like  the  teeth  of  a comb,  whence  the 
term  Septum  Pectiniforme. 

In  the  middle  of  the  corpus  cavernosum  above,  is  a 
longitudinal  sulcus  for  lodging  the  veins  of  the  penis, 
and  in  tlie  same  manner  below,  another  for  the  corpus 
spongiosum  urethrse.  The  cavity  of  this  membrane 
is  filled  by  a spongy  tissue,  w'hich  arises  from  its  inter- 
nal face,  and  is  formed  of  filaments  and  little  lamime ; 
they,  by  crossing  each  other,  form  a multitude  of  cells 
which  have  a perfectly  free  communication  with 
each  other,  and  generally  are  somewhat  occupied  by 
blood. 

The  Corpus  Spongiosum  Uretlirm  extends  from  tei; 


MALE  PELVIS. 


271 


or  twelve  lines  behind  the  junction  of  the  crura  of  the 
corpus  cavernosum,  to  the  anterior  extremity  of  the 
penis. . Externally  it  is  covered  by  a coat  resembling 
that  of  the  corpus  cavernosum,  except  that  it  is  thinner. 
In  its  centre  is  the  canal  for  the  urine.  Between  this 
canal  and  the  coat  is  a spongy  structure,  much  finer 
than  that  of  the  corpus  cavernosum,  and  though  the  cells 
communicate  freely,  still  they  have  the  appearance  of 
'convoluted  veins.  The  corpus  spongiosum  is  not  of  the 
same  thickness  in  its  whole  course ; its  commencement 
in  the  perineum  where  it  is  pendulous,  is  enlarged  into 
what  is  termed  its  Bulb,  from  this  it  diminishes  gi’adu- 
ally  to  the  end  of  the  corpus  cavernosum,  where  it  is 
again  enlarged  into  the  Gians  Penis.  The  transverse 
diameter  of  the  glans  being  larger  than  that  of  the  body 
of  the  penis,  it  forms  all  around  a projecting  shoulder, 
the  Corona  Glandis.  The  surface  of  the  glans  is  covered 
by  a very  delicate  epithelium,  and  has  a gi’eat  number  of 
papillae  for  the  distribution  of  nerves.  Numerous  folli- 
cles also  exist  about  the  corona  glandis,  to  secrete  the 
sebaceous  fluid  which  collects  there  in  persons  who  are 
not  cleanly. 

The  Urethra  is  a canal  whose  length  varies  accord- 
ing to  the  degree  of  erection  in  the  penis,  and  extends 
from  the  neck  of  the  bladder  to  the  extremity  of  the 
glans.  It  has  several  curvatures  and  receives  in  its 
course  the  ductus  ejaculatorii,  the  excretory  ducts  of 
Couper’s  glands,  and  the  mucous  lacunae  of  its  internal 
membrane.  The  first  part  of  this  canal  which  traver- 


272 


OF  THE  TRUNK. 


ses  the  prostate  gland  is  about  fifteen  or  eighteen  lines 
in  length;  it  is  the  Prostatic  Portion,  and  is  well  sup- 
ported by  this  body,  although  its  own  sides  are  very 
thin.  On  its  inferior  surface  is  the  Verumontanum  or 
Caput  Gallinaginis,  an  oblong  projection  of  the  lining 
membrane  an  inch  in  length,  broad  behind  where  it 
commences  a little  in  advance  of  the  Uvula  Vesicse,  and 
coming  to  a point  very  gradually  before.  In  the  pos- 
terior ridge  of  the  caput  is  a long  cleft,  which  is  the 
orifice  of  a large  lacuna  observed  first  by  Morgagni ; and 
on  the  front  surface  on  each  side,  is  the  orifice  of  the  ductus 
ejaculatorius.  On  the  sides  of  the  caput  gallinaginis  the 
canal  of  the  urethra  is  depressed  into  something  like  a 
cul-de-sac,  where  are  to  be  found  from  four  to  six  very 
small  orifices,  or  according  to  Loder  from  sixteen  to 
twenty-two,  belonging  to  the  lacunae  of  the  prostate 
gland. 

Between  the  Prostate  and  the  Bulb  is  the  Membra- 
nous Part  of  the  urethra,  about  eight  or  ten  lines  long; 
it  is  unprotected  except  by  a soft  covering  which  seems 
in  some  measure  to  be  a mixture  of  gelatinous  matter 
and  muscular  fibre.  The  former  was  considered  by 
Littre  as  a glandular  body  which  secreted  a viscid 
humour  into  the  interior  of  the  canal ; the  latter  pro- 
bably is  the  part  described  by  Winslow  as  the  infe- 
rior prostatic  muscle,  which  arising  on  each  side  of 
the  membranous  canal  goes  to  be  inserted  into  the  cor- 
responding branch  of  the  pubes  near  the  symphysis. 
The  membranous  part  of  the  urethra  does  not  get 


MALE  PELVIS. 


273 


iato  the  end  of  the  bulb,  but  penetrates  it  from  above, 
half  an  inch  or  more  occasionally,  from  its  extremity, 
just  below  the  junction  of  the  crura  of  the  Corpus 
Cavernosum. 

The  canal  varies  in  its  dimensions;  at  its  commence- 
ment at  the  bladder  it  is  large;  it  then  contracts  at  the 
back  of  the  caput  gallinaginis,  and  hnmediately  enlarges 
in  the  fore  part  of  the  prostate.  The  membranous  part 
is  small;  the  canal  then  enlarges  in  the  bulb.  In  the 
body  of  the  penis  the  canal  is  successively  diminished, 
till  it  comes  almost  to  the  glans,  when  it  is  so  remark- 
ably enlarged  as  to  get  the  name  of  Fossa  Navicularis; 
it  terminates  finally  by  a short  vertical  slit  at  the 
extremity  of  the  glans. 

In  the  whole  length  of  the  canal  there  are  two 
whitish  middle  lines,  one  above  and  the  other  below, 
•and  in  the  membranous  and  spongy  portions,  excep- 
ting the  fossa  navicularis,  longitudinal  folds  of  the 
lining  membrane  exist,  which  are  effaced  by  distention. 
In  the  upper  part  of  the  canal  there  are  a great  many 
mucous  lacunae;  Loder,  in  his  plates,  has  marked  about 
sixty-five;  there  is  one  particularly  large  in  the  upper 
surface  of  the  fossa  navicularis,  which,  it  is  said,  has 
stopped  the  point  of  a bougie  and  been  mistaken  for 
stricture.* 

* Sir  Everard  Home  has  lately  communicated  to  the  Royal 
Society  a highly  interesting  paper  on  the  structure  of  the  lining 
membrane  of  the  urethra.  From  his  microscopical  observa- 
tions, he  is  induced  to  tbink,  that  there  can  be  no  doubt  of  its 
Aiuscularity. 


M m 


274 


OF  THE  TRUNK. 


At  the  posterior  part  of  the  hulb  are  Couper*s 
Glands,  two  small  bodies  about  the  size  of  a garden 
pea.  Their  excretory  ducts  are  about  an  inch  long, 
and,  passing  very  obliquely  under  the  internal  mem- 
brane of  the  urethra,  they  terminate  at  the  anterior 
part  of  the  bulb,  in  the  lower  side  of  the  canal.  Other 
glands,  but  smaller,  of  the  same  kind  are  said  to  exist 
occasionally;  I have  never  seen  them  except  in  a pre- 
paration in  the  museum  of  Mr.  Bell  in  London.  Mor- 
gagni and  Couper  describe  them.  Marjolin  says  their 
existence  is  not  constant,  though  they  have  been  des- 
cribed by  many  anatomists. 

Mr.  Shaw  of  London  has  described  a set  of  vessels 
immediately  on  the  outside  of  the  internal  membrane 
of  the  urethra,  which,  when  empty,  are  very  similar, 
in  appearance,  to  muscular  fibres.  He  says  he  lias 
discovered  that  these  vessels  form  an  internal  spongy 
body  which  passes  down  to  the  membranous  part  of  the 
urethra,  and  forms  even  a small  bulb  there.  See  Med. 
Chir.  Trans,  vol.  x.  His  preparation,  being  a quick- 
silver injection  of  the  part,  is  certainly  a very  satisfac- 
tory demonstration  of  their  existence:  yet  in  my  own 
observations,  I have  not  been  able  to  distinguish  them 
from  the  cellular  membrane  connecting  the  canal  of  the 
urethra  to  the  corpus  spongiosum. 


MALE  PELVIS. 


27  5 


Of  the  Testicles,  ( Tester. ) 

These  bodies,  two  in  number,  are  surrounded  by 
several  coats,  the  most  external  of  which,  is  common 
to  both  the  testicles  and  is  called  Scrotum;  the 
others  are  proper.  The  scrotum  is  a sac  formed  by  a 
continuation  of  skin  from  the  internal  sides  of  the 
thighs,  from  the  inferior  part  of  the  penis,  and  from 
the  anterior  part  of  the  perineum.  It  is  very  thin, 
darker  than  the  rest  of  the  skin,  sparingly  covered 
with  hairs,  has  many  sebaceous  follicles  in  it,  and  is 
closely  united  to  the  cellular  membrane  beneath.  It 
is  very  extensible,  and  has  a great  power  of  contraction, 
its  surface  being  covered  with  w^rinkles  which  are 
more  apparent  when  it  is  contracted.  It  consists  of 
two  symmetrical  halves  marked  off  from  each  other  by 
an  elevation  of  skin,  the  Raphe,  w^hich  extends  from 
the  perineum  over  the  scrotum  along  the  inferior  sur- 
face of  the  penis  to  the  end  of  the  latter. 

Beneath  the  scrotum  is  the  Dartos,  a fibrous  mem- 
brane, which  is  vascular,  reddish,  and  deprived  of  fat ; 
it  arises  from  the  inferior  margins  of  the  crura  of  the 
ischia  and  pubes,  and  passing  downwards,  it  joins 
the  raphe ; it  is  then  reflected  upwards,  forms  a sep- 
tum between  the  two  sides  of  the  scrotum,  and  goes 
up  to  the  inferior  part  of  the  urethra.  This  mem- 
brane has  been  confounded  with  cellular  substance,  but 
it  appears  frpjn  the  reports  of  Messieui’s  Chaussier, 


276 


OF  THE  TRUNK, 


Lobsteiii,  and  Breschet^  that  it  does  not  exist  in  the 
scrotum  till  the  descent  of  the  testicle,  and  that  it  is 
an  expansion  of  the  gubernacuhmi  testis. 

Notwithstanding  its  great  contractility,  the  ques- 
tion of  its  muscular  structure  is  not  settled,  and  cer- 
tainly, ill  the  greater  part  of  its  extent,  there  is  not 
the  appearance  of  muscular  fibre,  but  at  its  poste- 
rior end,  just  at  the  anterior  point  of  the  sphincter 
ani,  I have  often  seen  a broad  muscular  expanse,  the 
character  of  which  could  scarcely  be  misconceived. 
The  contractility  of  the  scrotum  has  been  attributed 
to  the  cremaster  muscle  instead  of  to  this  membrane, 
but  common  observation  will  convince  most  pei'sons 
that  the  elevation  of  the  testicles  in  the  scrotum  by 
the  contraction  of  the  cremastei’s  is  very  distinguish- 
able from  that  contraction  of  the  scrotum  by  which 
the  testicle&are  squeezed  against  the  sides  of  the  pubes 
and  the  scrotum  brought  into  a hard  corrugated  mass. 

The  Cremaster  muscle  is  rjither  an  imperfect  coat ; 
its  course  has  been  explained  in  the  account  of  the 
abdominal  muscles.  Its  fibres  are  much  separated  on 
the  tunica  vaginalis;  they  lay  on  its  front  part,  and  oh  the 
internal  and  external  sides  of  the  spermatic  cord-  With- 
in the  last  is  a coat  of  cellular  substance  the  Tunica 
Vaginalis  Communis. 

The  Tunica  Vaginalis  Testis  was  originally  a pro 
cess  of  peritoneum,  though  it  appears  in  the  adult  as  a 
complete  sac.  The  testicle  being  protruded  into  ii 
from  behind,  one  half  of  the  sac  applies  itself  closely  to 


MALE  PELVIS. 


277 


the  epididymis  and  testicle,  while  the  other  half  is 
"loose;  the  whole  arrangement  being  precisely  after  the 
manner  of  the  double  night-cap  when  drawn  over  the 
head.  It  passes  up  some  distance  on  the  cord;  its  cavity 
is  smooth,  polished,  and  moistened  by  a.  synovial  haliius 
which  allows  the  surfaces  to  move  freely  upon  each 
other. 

The  Tunica  Albuginea  is  the  proper  coat  of  the 
testicle  which  preserves  its  form,  and  is  in  immediate 
contact  with  the  glandular  structure.  It  is  a dense, 
strong,  white,  and  fibrous  membrane,  corresponding 
very  much  in  its  general  characters  with  the  tunica 
sclerotica  of  the  eye.  From  the  internal  surface  of 
the  albuginea,  several  membranous  processes  forming 
partial  partitions  pass  off,  and  terminate  at  the  pos- 
terior part  of  the  cavity  in  the  Corpus  Highmorianiim. 
These  septulse  conduct  the  blood-vessels  through  the 
substance  of  the  gland,  and  form  little  apartments  filled 
up  by  the  seminiferous  tubes.  The  Corpus  Highmo- 
rianum  is  a longitudinal  projection  of  the  tunica  albu- 
ginea, somewhat  broader  above  than  below ; its  upper 
part  is  perforated  by  the  vasa  efferentia. 

The  form  of  the  Testicles  as  communicated  by  the 
tunica  albuginea,  is  very  much  that  of  an  oval,  some- 
what compressed  laterally,  the  edges  presenting  for- 
wards and  backwards;  they  do  not  hang  with  the  long 
diameter  vertical,  but  the  upper  end  is  advanced  a 
little  forwards,  and  the  lower  points  somewhat  back- 
wards. They  are  both  of  the  same  size  generally,  but 


278 


OF  THE  TRUNK. 


in  case  of  a difference  the  right  is  larger;  it  is  also 
higher  up  than  the  left,  a circumstance  which  has  been 
marked  by  sculptors  in  all  ages. 

The  glandular  structure  of  the  testicle  consists  of  a 
congeries  of  convoluted  tubes,  stated  by  Monro  to 
amount  to  three  hundred,  whose  diameters  do  not 
exceed  individually  the  one  two-hundredth  part  of  an 
inch,  and  when  extended  to  their  full  length,  would 
form  in  the  aggregate,  a tube  5208  feet  long.  These 
tubes,  almost  inconceivably  line  as  they  are,  can  be 
injected  in  a retrograde  course  through  the  vas  deferens 
with  mercury,  but  the  task  is  one  of  exceeding  diffi- 
culty, and  scarcely  ever  succeeds.  Such  preparations 
are  consequently  very  rare  in  anatomical  cabinets. 
Those  which  I have  noticed  particularly,  were  made  by 
Mr.  Shaw  of  London  for  the  Museum  of  Mr.  Bell, 
and  by  the  present  Professor  Sandifort,  for  the  col- 
lection at  Leyden.  Haller  has  introduced  the  plate 
of  one  in  his  Opusculum  Minus,  which  was  highly  dis- 
tinguished in  its  time,  but  in  this  the  mercury  does 
not  seem  to  have  pervaded  fully  the  tubuli  seminiferi, 
notwithstanding  which,  it  went  far  to  establish  the  struc- 
ture of  the  testis,  and  to  settle  the  dispute  in  regard  to 
the  organization  of  the  corpus  higbmorianum. 

The  Tubuli  Seminiferi,  it  has  been  stated,  fill  up 
nearly  the  whole  of  the  cavity  of  the  albuginea,  being 
kept  from  each  other  by  the  processes  termed  Septulse. 
These  tubes  send  out  a great  number  of  trunks,  which, 
from  their  observing  a straight  coui'se,  obtain  the  name 


MALE  PELVIS. 


279 


of  Vasa  Recta.  These  vasa  reeta  unite  and  form  a net- 
work, the  Rete  Testis.  From  the  rete  testis  there 
proceed  from  twelve  to  eighteen  tubes,  whieh  pass 
through  the  upper  part  of  the  eorpus  highmorianum, 
and  get  to  the  outside  of  the  tuniea  albuginea;  these 
are  the  Vasa  Elferentia.  Each  of  these  vasa  is  rolled 
iip  - externally  at  this  plaee,  so  as  to  give  the  outline 
pf  a cone,  therefore,  it  gets  the  name  of  Conus  Vascu- 
losus.  Each  cone  successively  empties  into  a single 
tube  on  the  back  of  the  testis,  which  is  prodigiously 
convoluted  and  forms  a large  body,  the  Epididymis. 

The  Epididymis  is  a prismatic  arch  enlarged  at  both 
extremities,  and  resting  vertically  on  the  back  of  the 
testicle,  being  connected  with  it  by  the  tunica  vagi- 
nalis. The  enlargement  above  is  the  Globus  Major, 
and  is  formed  of  the  coni  vasculosi,  but  what  remains 
of  this  body  below,  consists  of  one  tube  excessively  con- 
voluted. The  enlargement  below  is  the  Globus  Minor; 
after  this  is  formed,  the  tube  becomes  less  convoluted 
and  turns  upwards  on  the  inside  of  the  epididymis,  and 
a little  further  on  it  becomes  nearly  straight,  and  is 
called  Vas  Deferens.  There  is  a blind  duct  which, 
commences  at  the  top  of  the  epididymis  and  terminates 
below,  the  intention  of  which  is  not  known. 

The  Vas  Deferens  is  a white  tube  about  a half  line 
in  diameter,  having  a cartilaginous  feel;  its  cavity  is 
large  enough  to  admit  a bristle..  It  passes  on  the  back 

* It  is  sometimes  called  the  Vasculum  Aberrans  Halleri,  and 
is  said,  by  Mr.  Cruikshank,  to  be  an  anomaly. 


280 


OF  THE  TRUNK. 


of  the  spermatic  cord,  and  continues  with  it  through 
the  abdominal  canal;  at  the  internal  ring  it  leaves  the 
residue  of  the  cord,  and  dipping  into  the  pelvis  by  the 
side  of  the  bladder,  goes  between  it  and  the  ureter  to 
the  lower  fundus,  approaching  its  fellow  on  the  inside 
of  the  vesiculse  seminales,  and  ending  in  the  urethra. 
About  two  and  a half  inches  from  its  termination  it  be- 
comes somewhat  tortuous  and  enlarges. 

The  Spermatic  Cord  is  formed  of  the  Vas  Deferens, 
the  Spermatic  Artery  and  Veins,  Lymphatics,  Nerves, 
and  Cellular  Membrane,  all  covered  by  the  Cremaster 
muscle.  The  artery  arises  from  the  aorta  and  retains 
its  first  size  till  it  arrives  at  the  testis,  it  then  divides, 
some  of  its  branches  being  spent  on  the  epididymis, 
and  the  remainder  going  into  the  testis,  and  termina- 
ting on  the  tubes.  The  veins  in  ascending  form  a 
remarkable  plexus,  the  Corpus  Pampiniforme,  at  the 
internal  ring  they  unite  into  one  trunk,  which  on  the 
right  joins  the  ascending  cava,  and  on  the  left  the 
emulgent  vein. 

Having  thus  become  acquainted  with  the,  structure 
of  the  viscera  of  the  male  pelvis,  I advdse  tlie  student 
in  the  next  place  to  put  a subject  in  the  posture  recom- 
mended for  Lithotomy,  in  order  that  he  may  work  on 
the  Perineum, 


MALE  PELVIS. 


281 


Section  II. 

Of  the  Perineum  and  the  Fascise  of  the  Male  Pelvis. 

The  subject  being  fixed  in  the  posture  indicated, 
make  a horizontal  cut  through  the  skin,  at  the  junction 
of  the  raphe  of  the  perineum  with  tlie  scrotum,  ex- 
tending it  on  each  side  three  inches;  drop  perpendicu- 
lar cuts  equally  profound  with  the  first  from  both  of  its 
extremities,  to  a line  which  would  pass  horizontally 
through  the  point  of  the  os  coccygis.  The  skin  con- 
stituting this  flap  being  raised  up  carefully,  so  as  not  to 
injure  subjacent  parts,  the  structure  of  the  perineum  is 
sufliciently  opened  for  the  time. 

The  Perineal  Fascia  is  first  exposed;  it  occupies 
nearly  all  the  space  between  the  anus  and  the  posterior 
margin  of  the  scrotum,  (insensibly  blending  with  the 
latter,)  and  between  the  rami  of  the  pubes  and  of  the 
ischia,  being  very  firmly  fixed  to  these  bones.  This 
fascia,  in  case  of  rupture  in  the  posterior  part  of  the 
urethra,  prevents  the  urine  from  showing  itself  in 
the  perineum,  and  drives  it  into  the  cellular  struc- 
ture of  the  scrotum.  In  abscesses  of  the  perineum, 
it  also  prevents  the  fluctuation  from  being  very  evident. 
Having  studied  well  its  connexions,  structure  and  in- 
fluence, it  is  to  be  cleared  away  in  order  to  bring  into 
view  the  Perineal  Muscles. 


N n 


282 


OF  THE  TRUNK. 


The  Erector  Penis  is  so  situated  as  to  cover  the  whole 
of  the  crus  of  the  penis  which  is  not  in  contact  with  the 
bony  margin  of  the  pelvis.  It  arises,  therefore,  from 
the  anterior  part  of  the  tuber  ischii  tendinous  and 
fleshy,  its  fleshy  fibres,  adhering  to  the  internal  and 
external  margins  of  the  rami  of  the  pubes  and  ischium, 
proceed  upwards,  and,  just  before  the  union  of  the 
crura  of  the  penis,  end  in  a flat  tendon  which  is  lost 
on  the  side  of  the  elastic  membrane  of  the  penis. ^ 

Its  use  is  not  well  understood. 

The  Accelerator  Urinac  lies  on  the  bulb  and  back 
part  of  the  corpus  spongiosum  urethrae;  it  is  a thin 
muscle  consisting  of  oblique  fibres. 

It  arises  by  a pointed  production  from  the  side  of  the 
body  of  the  penis;  its  origin  is  continued  obliquely 
across  the  inferior  surface  of  the  crus  where  the 
latter  begins  to  form  the  body  of  the  penis.  It  arises 
also  from  the  inner  side  of  the  ramus  of  the  pubes  be- 
tween the  crus  penis  and  the  triangular  ligament  of  the 
urethra.  The  muscles  of  the  opposite  sides  are  insert- 
ed into  each  other  by  a white  line  which  marks  the 
middle  of  the  bulb  of  tlie  urethra,  and  by  a point  into 
the  anterior  extremity  of  the  sphincter  ani,  where  they 
are  joined  by  the  transversal es  perinei. 

In  order  to  see  the  origin  of  these  muscles  very  dis- 

* The  late  Dr.  Lawrance  informed  me  that  he  has  fi-equently 
found  muscular  fibres  between  the  bone  and  the  crus  penis. 


MALE  PELVIS, 


283 


tinctiy,  separate  them  from  each  other  in  the  middle 
line  and  dissect  them  from  the  corpus  spongiosum.  Cut 
transversely  through  the  corpus  spongiosum  about  three 
inches  before  the  triangular  ligament  and  dissect  it 
clearly  from  the  corpus  cavernosum,  turning  it  down- 
wards so  that  it  may  hang  by  the  membranous  part  of 
the  urethra.  By  putting  the  two  acceleratores  on  the 
stretch  it  will  be  seen  that,  besides  the  origins  men- 
tioned, they  arise  also  from  each  other  by  a tendinous 
membrane  that  is  interposed  between  the  corpus  spon- 
giosum and  cavernosum,  so  that  they  literally  surround 
the  bulb  of  the  urethra  constituting  a complete  sphinc- 
ter muscle  for  it. 

These  two  muscles  are  considered  by  M.  Chaussier 
as  forming  but  one;  in  that  case  its  origin  will  be  re- 
versed, and  commence  in  the  middle  line  of  the  peri- 
neum instead  of  terminating  there..  The  relation  of 
this  muscle  and  the  erector  penis  should  be  observed, 
in  order  to  appreciate  the  difficulty  of  getting  into  the 
membranous  part  of  the  urethra  in  lithotomy,  without 
cutting  through  the  muscular  fibres  of  one  or  the  other. 

It  propels  the  urine  and  semen  forward. 

The  Transversus  Perinei,  as  its  name  implies,  passes 
directly  across  the  perineum ; it  arises  from  the  inner 
side  of  the  tuber  ischii  just  at  the  origin  of  the  erector 
penis,  and  is  inserted  where  the  sphincter  ani  and 
the  acceleratores  join. 

I have  observed  that  when  the  lower  part  of  the 


284 


OF  THE  TRUNK. 


accelerator  was  extended  much  below  its  usual  line  and 
strongly  developed,  that  the  transversus  was  very  irre- 
gular in  its  origin  and  course,  consisting  frequently  of 
a few  fibres  which  did  not  deserve  the  name  of  a dis 
tinct  muscle,  and  were  almost  unappropriated  in  the 
adipose  matter  of  the  part. 

Occasionally  a fasciculus  of  muscular  fibres  exists, 
called,  by  Albinus,  Transversus  Periuei  Alter,  which 
arises  in  front  of  the  former  muscle,  and  is  inserted  into 
the  perineal  junction  just  behind  it. 

The  use  of  these  muscles  seems  to  be,  to  contribute 
to  fix  the  bulb  of  the  urethra. 

The  Sphincter  Ani  muscle  consists  in  a plane  of 
fibres  which  surrounds  the  anus  in  order  to  keep  it 
closed.  It  has  two  fixed  points,  the  last  bone  of  the 
os  coccygis  behind  and  the  perineal  union  of  the  other 
muscles  in  front;  its  lateral  diameter  occupies  about  one- 
half  of  the  space  between  the  tuberosities  of  the  ischia, 
as  it  is  in  the  middle  of  this  space. 

Besides  closing  the  orifice  of  the  rectum  it  will  draw 
the  bulb  of  the  urethra  backwards,  or  the  point  of  the 
os  coccygis  forwards. 

The  Coccygeus  muscle  rather  belongs  to  the  interior 
of  the  pelvis,  but  is  seen  well  enough  here.  It  arises 
by  a small,  tendinous,  and  fleshy  beginning  from  the 
spine  of  the  ischium,  and,  lying  on  the  anterior  face  of 
the  anterior  sacro  sciatic  ligament,  it  is  inserted  into 


MALE  PELVIS. 


285 


the  sides  of  the  last  bone  of  the  sacrum  and  into  all 
those  of  the  os  coccygis. 

It  draws  the  os  coccygis  forwards. 

The  Erectores  Penis,  Acceleratores  Urinse,  and 
Transversi  Perinei  are  now  to  be  removed.  A large 
quantity  of  adipose  and  cellular  matter  will  be  found  on 
the  side  of  the  reetum  between  it  and  the  parietes  of 
the  pelvis,  concealing  the  levatores  ani  muscles.  This 
fat  is  better  left  in  situ  for  the  present. 

The  muscles  being  removed,  the  bulb  of  the  urethra 
is  seen  to  great  advantage,  extending  in  the  middle  of 
the  perineum  almost  to  the  anus.  It  is  not  loose  and 
pendulous  as  described,  but  is  eonnected  by  its  superior 
face  to  the  Triangular  Ligament  of  the  urethra,  a mem- 
brane which  fills  up  the  space  below  the  sym.physis  of 
the  pubes.  This  ligament  is  a septum  between  the 
perineum  and  pelvis,  and,  when  closely  examined,  is 
seen  to  connect  itself  to  the  internal  edges  of  the  rami 
of  the  pubes  and  ischia  on  the  inner  posterior  sides  of 
the  crura  penis  as  far  down  as  the  origins  of  the  latter. 
At  its  lower  edge  its  ligamentous  character  is  not  so 
well  defined.  It  extends  from  the  top  of  the  pubic 
arch  downwards  to  the  line  mentioned,  filling  up  all  the 
intermediate  space  between  the  bones.  On  its  anterior 
surface  is  the  bulb  of  the  urethra,  and  just  at  the  extre- 
mity of  the  latter,  enclosed  by  the  ligament  and  adher- 
ing to  it,  are  Couper’s  Glands.  A perforation  exists  in 
it  through  which  passes  the  membranous  part  of  the 


286 


OF  THE  TRUNK. 


urethra;  to  get  a view  of  which  the  corpus  spougiosuni 
if  not  already  detached,  must  be  cut  through  an  inch 
anterior  to  the  symphysis  pubis;  dissected  carefully 
from  the  corpus  cavernosum;.  and  turned  down  on  the 
perineum.  The  opening  at  first  is  not  very  apparent 
m consequence  of  its  edges  being  continued  a little  dis- 
tance on  the  canal,  but  by  detaching  them  the  hole 
becomes  well  defined. 

Here  it  becomes  necessary  to  attend  to  the  relative 
situation  of  the  bulb,  and  of  the  membranous  part  of  the 
urethra.  The  former  has  just  been  described  going 
towards  the  anus,  the  latter  passes  upwards  towards  the 
neck  of  the  bladder,  they  consequently  form  a consi- 
derable angle  with  each  other,  and  the  membranous 
part  of  the  urethra  is  much  the  deeper;  the  recollec- 
tion of  which  is  all  important  in  lithotomy,  as  it  teaches 
us  to  avoid  the  one,  and  to  cut  into  the  other.  It  will 
also  be  observed  that  the  hole  in  the  triangular  liga- 
ment is  an  inch  below  the  symphysis  pubis. 

By  dissecting  off  the  upper  corner  of  the  triangular 
ligament,  we  are  made  acquainted  with  another  just 
behind  it  which  is  totally  distinct.  This  ligament  is 
half  an  inch  broad,  thick  and  strong  particularly  at  its 
lower  edge,  and  is  very  firmly  attached  laterally  to 
each  pubes  just  below  the  symphysis.  Mr.  Colles  calls 
it  pubic  ligament,  with  great  propriety;  I would  sug 
gest,  as  somewhat  more  expressive,  the  term  Inter-Pu- 
bic ligament,  as  it  serves  to  distinguish  it  from  another 


MALE  PELVIS. 


287 


called  pubic,  which  is  above  the  pubes.*  The  breadth 
of  this  having  been  stated  at  half  an  inch,  it  is  obvious 
that  the  hole  in  the  triangular  ligament  is  half  an  inch 
below  the  lower  edge  of  the  interpubic. 

We  have  now  seen  as  much  as  can  be  viewed  advan- 
tageously from  the  perineum  at  this  stage  of  the  dissec- 
tion, and  I recommend  an  inspection  of  the  parts  from 
above  on  the  side  of  their  abdominal  surfaces.  The 
pelvis  is  therefore  to  be  separated  from  the  trunk  at  the 
last  lumbar  vertebra  and  the  posterior  part  of  the  pel- 
vis to  be  removed,  sawing  through  the  os  ilium  from  its 
erista  to  the  upper  margin  of  the  sciatic  notch  on  each 
side;  the  os  coccygis  however  must  remain  in  situ,  as  it 
is  very  material  to  the  description  of  the  Levatores  Ani 
muscles.  Care  must  be  taken  not  to  iiyure  the  rectum 
in  these  sections. 

Begin  by  raising  the  peritoneum  from  the  anterior 
surface  of  the  rectum,  after  which  by  letting  the  rec- 
tum fall  backwards  and  putting  the  raised  peritoneum 
on  the  stretch,  an  excellent  view  is  obtained  of  the  line 
of  attachment  of  the  latter  to  the  lower  part  of  the 
bladder.  It  is  seen  that  the  peritoneum  is  reflected 
from  the  bladder  at  the  posterior  end  of  the  vesiculse 
seminales,  but  that  a pouch  or  process  of  it  is  sent 
down  between  them  which  reaches  to  a short  distance 
from  the  prostate  gland,  and  that  below  this  process  of  the 


* See  Abdominal  Muscles. 


288 


OF  THE  TRUNK. 


peritoneum,  a very  small  space  of  the  bladder  lies  naked 
which  can  he  punctured  from  the  rectum,  without  in- 
juring either  the  cavity  of  the  peritoneum  or  the 
vesiculsB  seminales. 

By  distending  the  bladder  moderately,  the  different 
reflections  of  the  peritoneum  from  it  to  the  abdominal 
parietes  and  to  those  of  the  pelvis  will  be  better  under- 
stood, and  the  possibility  of  puncturing  the  former 
above  the  pubes  without  getting  into  the  cavity  of  the 
abdomen  will  be  demonstrated  fully,  as  well  as  the 
freedom  with  which  its  neck  may  be  divided  in  the 
lateral  operation  for  the  stone. 

Next  strip  the  peritoneum  from  the  sides  of  the 
pelvis,  which  brings  into  view  the  Aponeurosis  Pelvica 
connecting  the  bladder  to  the  sides  of  the  pehds. 

This  fascia  descends  from  the  ilio-pectineal  line  to 
about  midway  in  the  depth  of  the  pelvis;  here  it  is 
reflected  from  the  surface  of  the  muscles  (the  Levatores 
Ani)  and  applies  itself  to  the  prostate  gland  and  blad- 
der, on  the  body  of  which  it  is  ultimately  lost.  At 
the  angle  of  its  reflection  this  fascia  appears  particularly 
strong  and  white,  but  becomes  more  weak  and  thin  as 
it  lines  the  muscles  and  covers  the  bladder.  In  tra- 
cing this  membrane  it  will  be  seen,  that  from  the  pubes 
just  below  the  symphysis,  a pointed  production  of  it 
constituting  its  anterior  margin  is  fixed  into  the  side  of 
the  neck  of  the  bladder.  This  pointed  production  on 
each  side  is  called  by  most  anatomists  the  Anterior 


MALE  PELVIS. 


289 


Ligaments  of  the  bladder.  Between  them  just  beneath 
the  symphysis  of  the  pubes  a pouch  large  enough  to 
receive  the  end  of  the  finger  is  formed  by  the  union  of 
the  fascige  of  the  two  sides;  this  pouch  connects  the 
middle  anterior  part  of  the  neck  of  the  bladder  to  the 
lower  margin  of  the  symphysis  pubis.^' 

A good  account  of  this  fascia  is  published  by  M. 
Breschet,  in  his  Thesis  on  Hernia,  p.  130,  presented 
to  the  Faculty  of  Medicine  in  Paris  for  the  place,  of 
Chef  des  Travaux  Anatomiques  in  the  year  1819. 
He  says,  “ that  when  the  aponeurosis  which  covers 
the  iliac  fossa  arrives  at  the  internal  margin  of  the 
iliacus  internus  and  psoas  magnus  muscles,  near  the 
superior  strait  of  the  pelvis,  it  plunges  into  this  cavity 
in  order  to  line  its  sides,  and  to  cover  the  muscles 
which  are  applied  on  its  several  openings.  Having 
got  very  low  down  it  embraces  the  rectum,  is  reflected 
upon  the  bas-fond  of  the  bladder,  the  prostate  gland, 
and  in  woman  upon  the  vagina.  From  which  cause 
these  viscera  may  be  said  to  be  in  part  in  the  cavity  of 
the  pelvis,  and  partly  out  of  it,  if  we  consider  this 
cavity  as  the  space  on  the  outside  of  the  aponeurosis. 
Some  practitioners  have  observed,  that  the  consequen- 
ces of  the  operation  of  lithotomy  are  different  when, 
the  instrument  penetrates  more  or  less  deeply  behind 
or  on  the  side.  Inflammations,  suppurations,  abscesses 
in  the  cavity  of  the  pelvis  occur  when  the  instrument 
is  thrust  in  too  much,  while  no  such  accidents  follow  an 
instrument  introduced  moderately  deep.  Some  dis- 


290 


OF  THE  TRUNK. 


tinguished  practitioners^  have  asked  the  reason  of 
these  differences;  and  I believe  that  I have  found  them 
in  the  arrangement  of  the  aponeurosis  pelvica.  If  the 
instrument  does  not  penetrate  beyond  this  fascia,  there 
is  no  abscess  in  the  pelvis,  or  if  a small  quantity  of  pus 
be  formed,  it  readily  finds  an  issue  externally.  On 
the  contrary,  if  the  pelvic  aponeurosis  be  injured, 
inflammation  developes  itself,  suppuration  takes  place 
beyond  this  aponeurotic  barrier,  the  liquid  cannot  get 
out,  and  it  makes  ravages  which  sometimes  cause  the 
death  of  the  patient.” 

This  description  of  the  aponeurosis  pelvica  is  true, 
but  rather  too  general;  the  most  common  condition 
of  it  is  found  to  be  as  follows.  It  adheres  closely  to 
the  peinosteum  of  the  pubes  between  the  upper  mar- 
gin of  the  thyroid  foramen  and  the  crista  of  the  pubes: 
about  the  middle  third  of  the  linea  innominata  it  is 
obviously  a continuous  membrane  with  the  iliac  fascia, 
but  behind  this  again  it  arises  from  the  remaining  third 
of  the  linea  innominata. 

The  portion  of  this  fascia  which  Mr.  Colles  speaks 
of  as  particularly  strong  and  white,  forms  a bow,  the 
concavity  of  which  looks  upwards,  one  end  of  the  bow 
being  fastened  to  the  pubes  above  the  foramen  thyroi- 
deum,  and  the  other  end  to  the  ischium  above  its  spine. 
The  perineal  surface  of  this  bow  is  an  important  point 
of  the  origin  of  the  levator  ani.  Above  the  bow  this 

\ 

Scarpa's  IMemoir  on  Hawkins'  Gorget- 


MALE  PELVIS. 


291 


lasck  is  very  thinj  for  the  fibres  of  the  obturator  inter- 
ims can  be  readily  seen  through  it. 

At  the  bow  this  fascia  divides  into  two  laminae,  one 
having  the  course  to  the  bladder  and  rectum  indicated, 
the  other  covers  the  lower  part  of  the  obturator  iuternus 
muscle  and  constitutes  the  obturator  fascia.  The  levator 
ani  is  interposed  between  the  laminae.  The  aponeurosis 
pelvica  also  forms  a bow  or  semilunar  edge  in  front  of 
the  sacral  nerves. 

The  Levator  Ani  muscle  is  essentially  connected  with 
the  aponeurosis  pelvica.  In  order  then  to  get  a view 
of  it,  make  a cut  through  the  fascia,  from  the  symphy- 
sis pubis  backwards  to  the  sciatic  notch  about  half  an 
inch  above  the  middle  of  the  fascia.  As  the  muscle 
is  placed  nearer  to  the  perineum,  the  fascia  must  be 
turned  down  towards  the  bladder  as  low  as  possible, 
the  upper  surface  of  the  muscle  is  thus  exposed,  and 
also  the  manner  in  which  it  may  be  said  to  arise,  par- 
ticularly at  its  posterior  part  from  the  under  or  peri- 
neal surface  of  the  fascia.  '' 

The  Levator  Ani  muscle  arises  fleshy  from  the  back 
of  the  pubes  near  its  symphysis,  and  from  near  the  su- 
perior margin  of  the  foramen  thyroideum  above  the 
obturator  internus  muscle.  It  also  arises  from  the 
aponeurosis  pelvica,  where  this  membrane  is  extended 
as  a thickened  semilunar  cord  from  the  superior  margin 
of  the  thyroid  foramen  to  the  margin  of  the  sciatic 
notch.  This  second  part  of  the  origin  of  the  levator 


292 


OF  THE  TRUNK. 


ani  is  defectively  described  in  most  books  on  anatomy. 
It  is  then  seen  to  cross  obliquely,  as  far  as  the  spine  of 
the  ischium,  that  portion  of  the  obturator  internus 
which  arises  from  the  plane  of  the  ischium. 

From  this  extensive  origin  the  fibres  converge, 
descend  backwards,  afid  have  three  distinct  places  of 
insertion;  the  posterior  fibres  are  inserted  into  the  two 
last  bones  of  the  os  coccygis;  the  middle,  and  by  far  the 
greater  number  are  inserted  into  the  semi-circumference 
of  the  rectum  between  its  longitudinal  fibres  and  the 
circular  fibres  of  the  sphincter  ani;  and  finally,  the  most 
anterior  fibres  pass  obliquely  downwards  and  backwards 
on  the  side  of  the  vesical  end  of  the  membranous  part 
of  the  urethra,  and  on  the  side  of  the  prostate  gland, 
and  are  inserted  into  the  common  point  of  the  perineal 
muscles.  These  insertions  of  the  levatores  ani,  to  be 
well  understood,  must  be  studied  both  from  the  peri- 
neal and  abdominal  surfaces. 

It  yet  remains  to  speak  more  definitively  of  theTri 
angular  Ligament;  it  has  been  seen  from  the  perineum, 
and  is  now  to  be  viewed  from  the  pelvis.  Remove  the 
anterior  part  of  the  levatores  ani;  the  ligament  is  then 
seen  occupying  the  interval  under  the  symphysis  and 
between  the  rami  of  the  pubes  and  ischia,  extending 
dowmvards  an  inch  and  a half.  Its  base  or  inferior  edge 
is  crescentic,  and  half  an  inch  above  the  base  is  the 
hole  for  the  membranous  part  of  the  urethra.  This  hole 
is,  in  fact,  not  very  distinct,  for  the  triangular  ligament 


MALE  PELVIS. 


293 


IS  reflected  backwards  from  its  edges  along  the  mem- 
branous part  of  the  urethra,  which  obscures  the  hole. 
The  prostate  gland  also  gets  a ligamentous  capsule  from 
a continuation  of  this  same  reflection,  and  is  thereby 
very  firmly  fixed  in  its  place. 

The  edges  of  the  triangular  ligament,  fastened  to  the 
side  of  the  pubic  arch,  are  continuous  with  the  fascia 
covering  the  obturator  internus  muscle.  The  triangular 
ligament  is  a membrane  consisting  Of  two  laminae;  the 
bulb  of  the  urethra  is  fastened  to  the  anterior  lamina, 
and  the  prostate  gland  is  fixed  to  tlie  posterior  lamina; 
between  these  laminae  above  is  the  interpubic  ligament, 
and  several  blood-vessels  derived  from  the  vena  ipsius 
penis. 

Mr.  Colles  says:  If  we  attempt,  in  conformity  to 

the  custom  of  anatomical  writers,  to  describe  all  these 
continuous  fasciae  which  connect  the  bladder  and  ure- 
thra to  the  pubes,  as  . productions  of  one  and  the  same 
fascia,  we  might  say  that  the  triangular  ligament,  by  its 
outer  edges,  is  fixed  into  the  rami  of  the  pubes  and  is 
there  continuous  with  the  ligament  lining  the  obturator 
muscles,  that  the  edge  of  the  opening  for  receiving  the 
membranous  portion  of  the  urethra  is  produced  back- 
ward along  the  prostate,  and  having  ascended  as  high 
as  the  arch  of  the  pubes,  it  there  splits  into  two  lami- 
nae, one  continuing  its  course  over  the  upper  surface  of 
the  gland  and  bladder,  the  other  lining  the  upper  por- 
tion of  the  levator  ani.” 


294 


OF  THE  TRUNK. 


The  description  of  the  fasciae  of  the  pelvis  is  one  of 
the  most  difficult  and  perplexing  in  the  whole  range  of 
anatomy,  and  the  proof  of  it  is,  that  almost  every  wri- 
ter on  the  subject  considers  the  labours  of  his  prede- 
cessors imperfect,  and,  with  a very  laudable  spirit, 
hoping  to  supply  the  defect,  invites  the  attention  of  the 
profession  to  his  improved  views.  Not  joining  in  this 
conviction,  of  the  insufficiency  of  preceding  descrip- 
tions, and  the  consequent  value  of  such  as  ai'e  offered 
as  substitutes,  I feel  satisfied  in  drawing  materials  from 
Mr.  Colles’s  excellent  work  on  Surgical  Anatomy. 
Here  I may  express  a regret  that  a gentleman  whose 
views  are  so  luminous  on  a most  intricate  subject, 
should  have  confined  his  descriptive  talents  within 
such  small  boundaries  as  those  of  his  Surgical  Anatomy 


PART  II. 


CHAPTER  IV. 

Of  the  Organs  in  the  Female  fm'  the  Generation  and 
JVourishment  of  the  Infant. 


Section  I. 

Of  the  Female  Pelvis. 

The  viscera  of  the  female  pelvis  should  be  first 
studied  in  their  natural  situations;  they  should  then  be 
removed  and  dissected  neatly  for  more  satisfactory  ex- 
amination. The  whole  study  may  afterwards  be  con- 
cluded with  a side  view,  as  in  the  male  subject. 

The  Female  Pelvis  contains  the  Urinary  Bladder  and 
Rectum,  besides  the  Organs  of  Generation.  The  two 
first  do  not  demand  particular  description  here,  as 
enough  has  been  said  concerning  them  in  the  account 
of  the  male  pelvis.  The  Organs  of  Generation  are  si- 
tuated between  them,  and  consist  of  the  Vulva  exter- 
nally, of  the  Vagina  in  the  middle,  and  of  the  Uterus 
with  its  appendages  internally. 


296 


OF  THE  TRUNK. 


Under  the  term  Vulva  we  consider  the  Mens  Vene- 
ris, the  Labia  Majora  or  Externa,  the  Labia  Minora  or 
Interna,  the  Clitoris,  the  Vestibulum,  the  Orifice  of  the 
Urethra,  the  Foiirchette,  and  the  Fossa  Navicularis. 

Of  the  Vulva. 

The'MoNS  Vexeris  is  an  eminence  on  the  fore  part 
of  the  pubes  which  is  produced  by  the  deposit  of  a 
great  quantity  of  fat  under  the  skin.  In  very  corpu- 
lent women  its  size  is  occasionally  enormous.  The 
skin  covering  it,  at  the  age  of  puberty,  is  studded  with 
hair,  , and  under  it,  is  a considerable  number  of  seba- 
ceous glands. 

The  Labia  Externa  are  oblong  eminences,  continued 
downwards  and  backwards,  one  on  each  side,  from 
the  mons  veneris,  and  unite  with  each  other  by  the 
fourchette  at  the  anterior  part  of  the  perineum. 
They  are  produced  in  the  same  way  mth  the  mons 
veneris  by  a deposit  of  adipose  matter  beneath  the 
skin  or  integuments;  they  are  broader  and  more 
prominent  above  than  below^  On  the  side  which  looks 
to  the  thighs  they  are  formed  by  the  common  skin,  fur- 
nished sparingly  with  hairs;  but  on  the  internal  face  the 
integument  is  a mucous  membrane,  being  a continua- 
tion of,  that  of  the  vagina.  These  bodies  have  many 
sebaceous  glands  externally,  and  mucous  orifices  inter- 
nally on  them.  In  their  interior  structure  much  cellu- 


FEMALE  PELVIS. 


297 


iar  membrane,  like  that  of  the  scrotum,  is  found  pos- 
sessed of  great  extensibility  in  order  to  favour  the 
dilatation  of  the  parts  in  parturition.  Between  them 
is  a longitudinal  rima  about  twice  the  length  of  the  ori- 
fice of  the  vagina  for  favouring  still  more  the  expulsion 
of  the  foetus.  It  is  the  Fissura  Vulvae  of  authors. 

The  Clitoris  is  a small  body  situated  between  the 
upper  extremities  of  the  labia  externa  on  the  lower 
part  of  the  symphysis  pubis,  and  corresponding  with 
the  male  penis.  It  is  furnished  with  a suspen- 
sory ligament,  and  curved  tow^ards  the  urethra.  It 
consists  of  a body  and  of  two  crura;  the  body  is 
about  an  inch  long,  and  the  crura  being  of  the  same 
length,  arise  from  the  internal  faces  of  the  crura 
of  the  pubes.  It  is  covered  by  an  elastic  ligamentous 
membrane;  has  an  internal  spongy  body  capable  of 
erection  like  the  penis,  divided  by  a-septum  pectini- 
forme,  and  having  a similar  supply  of  blood-vessels  and 
of  nerves.  It  has  also  an  erector  clitoridis  muscle 
lying  upon  each  crus  and  extended  to  the  side  of  its 
body  in  the  same  way  with  the  erector  penis. 

The  extremity  of  the  body  of  the  clitoris  projects  into 
the  upper  part  of  the  bottom  of  the  rima,  and  is  called 
its  Gians,  but  does  not  resemble,  in  structure,  the 
glans  penis.  A kind  of  hood  is  thrown  over  it  by  a 
duplicature  of  the  integuments  of  the  part,  which  giving 
some  resemblance  to  the  penis,  it  is  therefore  called 
the  Prepuce,  (Preputium.)  This  prepuce  is  occasion- 

pp 


298 


OF  THE  TRUNK. 


ally  much  elongated  and  its  orifice  constricted,  so  that 
the  secretion  from  its  cryptae  is  imperfectly  discharged 
and  produces  much  itching  and  irritation.  Mr.  Mar- 
jolin  relates  the  case  of  a Spanish  girl  of  four  yeai-s,  in 
whom  he  performed  circumcision  successfully,  in  order 
to  free  her  of  a very  had  habit  to  which  she  was  ad- 
dicted in  consequence  of  this  disease. 

The  Labia  Interna,  or  Nymph;e,  are  two  mem- 
branous productions  passing  downwards,  one  from  each 
side  of  the  prepuce.  They  arise  from  the  internal 
sides  of  the  labia  majora,  are  seldom  so  broad  naturally 
as  to  project  beyond  them,  and,  are  wider  in  the 
middle  than  elsewhere;  they  terminate  insensibly  about 
half-way  down  the  orifice  of  the  vagina.  They  consist 
of  a duplicature  of  the  mucous  membrane  of  the  part, 
between  the  laminse  of  which  is  placed  a vascular  cel- 
lular membrane  giving  to  them,  when  excited,  a some- 
what erected  condition.  In  young  subjects  their  vas- 
cularity communicates  a vermilion  tint,  which  is  lost 
in  the  progress  of  life.  They  are  supposed  to  direct, 
in  some  measure,  the  stream  of  urine;  but  it  is  more 
probable  that,  as  they  are  efiaced  during  parturition, 
they  are  intended  to  facilitate  the  enlargement  of  the 
vulva. 

The  Vestibulum  is  the  depression  at  the  upper 
part  of  the  rima,  bounded  by  the  clitoris  above  and 
the  nymphae  laterally;  in  it  are  many  mucous  follicles. 


FEMALE  PELVIS. 


299 


At  the  inferior  part  of  the  vestibuhim,  about  an 
inch  below  the  glans  clitoridis,  is  the  Orifice  of  the 
Urethra,  (Orificium  Urethrae.)  It  is  generally  marked 
by  a slight  rising  or  tubercle  which,  is  easily  distin- 
guished by  the  sensation  of  touch  alone;  its  margin 
is  often  bounded  by  a little  caruncle  on  each  side.  The 
urethra  itself  is  an  inch  long,  larger  and  much  more 
dilatable  than  that  of  the  male;  its  course  is  obliquely 
downwards  and  forwards  from  the  neck  of  the  blad- 
der; passing  under  the  symphysis  of  the  pubis,  and  be- 
ing slightly  curved  from  that  cause.  It  consists  of 
two  membranes,  a lining  and  an  external  one.  The 
lining  membrane  is  a continuation  of  that  of  the  blad- 
der; is  thrown  into  several  longitudinal  folds,  and  has 
many  mucous  follicles  in  it.  The  external  coat  of  the 
urethra  consists  of  condensed  laminated  cellular  mem- 
brane, forming  a cylindrical  body  of  half  an  inch  in  its 
transverse  diameter,  which  has  given  the  idea  of  the 
existence  of  a prostate  gland  in  the  female.  The 
lower  and  lateral  surfaces  of  this  cylinder  are  in  con- 
tact with  the  vagina,  forming  a protuberance  into  its 
cavity,  and  the  upper  surface  is  firmly  connected  to 
the  triangular  ligament  of  the  pubes. 

The  Fourchette,  or  Frenulum  Vulvje,  is  situa- 
ted at  the  inferior  junction  of  the  labia  externa;  it  is  a 
narrow  duplicature  of  skin  extending  across  the  vulva 
from  one  side  to  the  other,  and  is,  most  frequently, 
ruptured  at  the  first  parturition  and  disappears.  That 


300 


OF  THE  TRUNK. 


portion  of  the  rima,  betwixt  it  and  the  orifice  of  the 
urethra,  is  called,  by  many  anatomists,  the  Fossa 
Navicularis. 

Of  the  Vagina. 

The  Vagina,  is  the  intermediate  part  of  the  sexual 
organs,  extends  from  the  Vulva  to  the  Uterus,  being 
placed  between  the  Bladder  and  Rectum,  and  com- 
pressed anteriorly  and  posteriorly  by  them.  In  vir- 
gins its  external  extremity  is  contracted  into  a smaller 
canal  than  the  internal,  and  besides  this,  is  closed  by  a 
membrane  called  the  Hymen. 

The  Hymen,  situated  just  within  the  orifice  of  the 
vagina,  is  a partial  septum  formed  by  a reflection  or 
duplicature  of  its  lining  membrane:  it  varies  very  much 
in  shape,  breadth,  and  thickness.  Most  commonly  it 
is  crescentic  and  fixed  to  the  inferior  part  of  the 
vaginal  orifice  by  its  convex  edge,  the  horns  being 
upwards;  in  other  cases  it  is  to  the  side.  Sometimes 
it  is  a circular  membrane  having  a hole  in  the  centre. 
It  is  generally  so  weak  that  it  is  ruptured  at  the  first 
act  of  copulation,  but  occasionally  so  resisting  that  it 
has  required  artificial  division  to  make  it  yield  even  to 
the  expulsive  efforts  of  the  uterus  in  parturition.  Its 
presence  then  is  not  invariably  a proof  of  virginity, 
nor  is  its  absence  a proof  of  improper  indulgence. 


FEMALE  PELVIS. 


301 


The  vagina  is  a membranous  canal  of  from  four  to 
six  inches ' in  length,  dilfering  according  to  age  and 
pregnancy,  being  much  shorter  in  women  who  have 
borne  children  than  in  virgins.  Its  shape  varies  some- 
what, near  the  vulva  its  greatest  diameter  is  vertical, 
but  behind  near  the  uterus  the  greatest  diameter  is 
transverse.  Its  anterior  and  posterior  surfaces  are  in 
contact  from  the  circumstances  just  mentioned  of  pres- 
sure between  the  bladder  and  the  rectum.  It  is  shorter 
before  than  behind,  corresponding  in  this  respect  with 
the  pelvis  by  which  it  is  influenced,  and  also  in  conse- 
quence of  being  attached  to  the  uterus  higher  up  on 
the  sacral  than  on  the  pubic  side. 

The  peritoneum,  in  descending  from  the  uterus  an- 
teriorly, touches  the  top  of  the  vagina  for  a little  dis- 
tance, and  is  then  reflected  to  the  bladder,  but  poste- 
riorly, nearly  the  upper  half  of  the  vagina  has  a 
peritoneal  coat,  before  this  membrane  is  reflected  to 
the  rectum.  The  attachment  of  the  vagina  to  the 
bladder  is  strong  and  close  just  about  the  urethra,  but 
its  connexion  to  the  rectum  is  by  rather  loose  cellular 
membrane. 

It  consists  of  two  coats,  a fibrous  and  elastic  one 
externally,  and  a mucous  one  internally.  The  first  is 
of  a reddish  colour,  and  seems  to  be  formed  of  con- 
densed cellular  membrane,  its  fibres  not  passing  in  any 
determinate  direction.  Many  blood-vessels  are  found 
in  its  structure,  and  it  has  an  abundance  of  large 
venous  sinuses  surrounding  it. 


302 


OF  THE  ITIUNK. 


On  the  anterior  part  of  this  coat  externally,  there  is 
a flat  spongy  body,  (Corpus  Spongiosum  Vaginae,) 
about  one  inch  broad  and  a line  or  two  thick,  which  is 
placed  on  its  superior  and  lateral  surfaces,  covering 
about  one-half,  or  two-thirds  of  the  whole  circumfe- 
rence of  the  vagina.  The  structure  of  the  body 
closely  resembles  that  of  the  corpus  spongiosum  ure- 
thrae, and  from  being  very  vascular,  is  subject  to  dis- 
tention in  its  cells  during  sexual  excitement.  This 
body  is  covered  by  the  sphincter  vaginae  muscle. 

The  Sphincter  Vaginse  arises  from  the  body  of  the 
clitoris,  forms  an  expanse  of  an  inch  and  a quarter 
around  the  anterior  end  of  the  vaginae,  and  is  inserted 
into  a dense  whitish  substance  in  the  centre  of  the 
perineum,  common  to  it,  the  sphincter  ani  aiid  the 
transversi  perinei  muscles. 

The  transverse  perineal  muscles  exist  in  the  female, 
and  have  the  same  circumstances  of  origin  and  insertion, 
but  are  not  so  strong  as  in  the  male. 

Anterior  to  the  corpus  spongiosum  on  each  side  of 
the  vagina,  near  its  middle,  is  a mucous  gland,  about 
the  size  of  a garden  pea,  which  is  the  Couper’s  gland 
of  the  female. 

To  bring  into  view  satisfactorily  the  internal  mem- 
brane of  the  vagina,  the  canal  should  be  slit  up  laterally 
from  its  external  orifice  to  the  uterus;  this  membrane 
being  mucous  will  then  be  observed  as  continuous  with 
the  mucous  membranes  of  the  vulva  and  uterus. 
Near  the  vulva  it  is  of  a vermilion  tinge,  but  near  the 


FEMALK  PELVIS. 


303 


uterus  it  is  greyish  with  several  dark  spots  giving  it  a 
marbled  appearance;  its  thickness  diminishes  as  it 
recedes  from  the  external  orifice. 

In  females  in  whom  the  hymen  is  ruptured,  its 
remains  consist  in  from  two  to  six  small  tubercles,  the 
Carunculas  Myrtiformes.  On  its  anterior  or  pubic  wall 
the  internal  surface  of  the  vagina  is  divided  longitu- 
dinally by  a ridge,  commencing  in  a sort  of  tubercle  at 
the  anterior  orifice  of  the  vagina  just  under  the  meatus 
urinarius;  this  ridge  proceeds  backwards,  but  becomes 
indistinct  in  approaching  the  uterus;  from  it  on  each 
side  proceed  transverse  ridges  or  folds  of  the  mucous 
membrane,  which  are  particularly  numerous  and  pro- 
minent before,  but  become  indistinct  and  irregular  near 
the  uterus.  The  inferior  side  of  the  vagina  has  the 
same  sort  of  arrangement  as  the  superior,  only  not  so 
well  marked. 

By  cleaning  the  vagina  and  suspending  it  in  water, 
an  abundance  of  mucous  cryptae  may  be  observed  oh  its 
whole  internal  surface,  which  by  an  increased  discharge 
produce  leucorrhoea. 

The  Uterus  and  its  Appendages,  the  Fallopian  Tubes 
and  Ovaria. 

The  Uterus  is  a compressed  pyriform  body  with  a 
cavity  in  its  centre,  is  placed  between  the  blad- 
der and  rectum,  has  the  small  intestines  above  it, 
and  the  vagina  below.  Unimpregnated  it  is  two  inches 


304 


OF  THE  TRUNE. 


and  a half  long,  and  an  inch  and  a half  wide  at  its  broad- 
est part;  its  anterior  surface  is  much  flatter  than  the 
posterior.  It  is  divided  into  fundus,  body,  and  neck. 
The  fundus  is  the  superior  convex  edge,  the  neck  the 
narrow  part  below  about  an  inch  long,  and  the  body  the 
portion  between  these  two. 

The  uterus  is  maintained  in  its  situation  in  the 
centre  of  the  pelvis  by  the  reflections  of  the  perito- 
neum, which  are  called  ligaments.  The  peritoneum, 
after  covering  the  uterus  completely  is  reflected  ante- 
riorly upon  the  vagina,  and  at  each  side  of  this  reflec- 
tion is  a fugitive  duplicature  of  the  membrane  denomi- 
nated the  Anterior  Ligament,  which  goes  to  the  blad- 
der. The  peritoneum  in  passing  from  the  back  part 
of  the  uterus  to  the  vagina  and  subsequently  to  the 
rectum,  has  on  each  side  of  this  reflection  also  a dupli- 
cature, which  constitutes  the  Posterior  Ligament. 
The  peritoneum  is  also  reflected  from  the  whole  length 
of  each  side  of  the  uterus  to  the  corresponding  part  of 
the  cavity  of  the  pelvis;  these  reflections  are  termed 
the  Lateral  or  the  Broad  Ligaments.  The  peritoneum 
covers  much  more  of  the  vagina  posteriorly,  than  it 
does  anteriorly. 

These  Broad  Ligaments,  with  the  uterus,  form  a 
transverse  septum  in  the  middle  of  the  pelvis.  At 
the  superior  edge  of  this  septum,  on  each  side,  is  the 
Fallopian  Tube,  and  on  the  posterior  face  of  the  sep- 
tum, below  the  edge,  and  about  an  inch  or  a little  more 
fi’om  the  uterus,  on  each  side,  is  an  Ovarium.  The 


FEMALE  PELVIS. 


305 


peritoneum  adheres  to  the  uterus  by  a cellular  tissue, 
which  is  somewhat  loose  and  can  be  easily  dissected 
from  it. 

Besides  the  ligaments  mentioned,  the  uterus  has  two 
more,  one  on  each  side,  called  the  Round  Ligaments. 
They  arise  from  the  side  of  its  body,  between  the  du- 
plicatures  of  the  broad  ligaments,  ^nd  pass  under  the 
peritoneum  to  the  abdominal  ring,  through  which  they 
penetrate,  and  are  lost  upon  the  fat  of  the  mons  veneris 
and  of  the  labia  majpra.  They  are  of  a fibrous  struc- 
ture, and  have  many  blood-vessels  in  them. 

The  neck  of  the  uterus  is  enclosed  by  the  cavity  of 
the  vagina,  in  such  a way  that  it  projects  into  the  latter. 
In  the  centre  of  this  projection  is  the  Orifice  of  the 
Uterus,  (Os  Tincse,)  which  is  not  perfectly  cylindrical 
but  somewhat  flattened  or  oval;  this  orifice  is  bounded 
before  and  behind  by  the  lips  or  projections  of  the 
neck,  which  are  transverse.  The  posterior  lip  is  some- 
what thinner  than  the  anterior,  but,  in  consequence  of 
the  insertion  of  the,  vagina  on  that  side  being  higher 
up,  it  projects  more  into  the  vagina,  and  is  easily  dis- 
tinguished by  the  finger. 

Behind  the  os  tincse  is  the  Cavity  of  the  Neck,  which 
is  a paraboloid  cylinder,  larger  in  the  middle  than  at 
either  end;  its  termination  forwards  is  about  the  size  of 
a small  writing  quill,  the  posterior  extremity  is  some- 
what larger.  In  the  middle  of  this  cavity,  before  and 
behind,  longitudinally,  is  a line  formed  by  an  elevation 
of  the  lining  membrane,  and  on  each  side  of  this  line, 

Q q 


306 


OF  THE  TRUNK. 


transversely,  there  are  others  presenting  an  arborescen: 
arrangement.  Tliis  is  the  Arbor  Vitse.  In  the  inter- 
stices of  the  transverse  lines  there  are  small  mucou.'; 
glands  called  Ovula  Nabothi,  in  consequence  of  thi^ 
anatomist  mistaking  them  for  eggs. 

The  cavity  of  the  body  of  the  uterus  is  triangular, 
the  sides  of  the  triangle  being  curved  inwards  so  as  to 
present  their  convexities  to  its  cavity.  The  cavity  is 
nearly  equilateral,  and  has  its  anterior  and  posterior 
surfaces  in  contact;  the  angle  below  is  continued  into 
the  cavity  of  the  neck,  and  the  angles  above  are  con- 
tinuous with  the  fallopian  tubes,  being  extended  very 
kir  through  the  parietes  of  the  uterus  in  order  to  meet 
them.  This  cavity  is  .sometimes  divided  into  two  sym- 
metrical halves  by  an  elevated  line  on  its  antenor  and 
posterior  surface,  running  from  above  downwards.  It 
is  said,  that  in  some  cases,  they  have  formed  a complete 
partition. 

The  internal  membrane  of  the  uterus  is  a continua- 
tion of  that  of  the  vagina,  and  adheres  so  closely  that 
its  existence  has  been  doubted.  It  has  very  little  thick- 
ness, is  extremely  smooth,  and  presents  villosities  so 
fine,  that  they  are  seen  with  difficulty  by  the  naked  eye. 
It  is  of  a light  pink  colour,  which  changes  into  a deeper 
vermilion  a few  days  before  and  during  menstruation. 
It  abounds  with  mucous  cryptse  and  exhalent  orifices. 

The  texture  of  the  uterus  is  essentially  fibrous  aiul 
of  a white  colour  tinged  with  red,  from  having  a great 
number  of  blood-vessels  in  its  composition.  The  fibres 


FEMALE  PELVIS. 


307 


have  no  determinate  course,  but  are  blended  and  inter- 
woven in  every  direction.  Its  muscularity  is  not  ap- 
parent in  the  unimpregnated  state. 

The  Fallopian  Tubes,  (Tubae  Uterinse,)  are  two 
membranous  canals  fixed,  as  mentioned,  in  the  upper 
edges  of  the  broad  ligaments.  They  are  about  four 
inches  long,  somewhat  serpentine,  and  extend  from  the 
upper  angles  of  the  uterine  cavity  to  the  sides  of  the 
pelvis.  At  their  uterine  extremities  these  tubes 
scarcely  admit  a hog’s  bristle,  but  as  they  proceed  ex- 
ternally, about  half-way  of  their  length,  they  begin  to 
increase,  and  continue  to  do  so  very  rapidly  almost  to 
their  termination,  where  they  become  somewhat  con- 
tracted, and  immediately  afterwards  enlarge  to  end  by 
an  oblique  trumpet  shape  mouth,  singularly  fringed, 
called  Morsus  Diaboli,  or  Corpus  Fimbriatum.  This 
latter  part  of  the  tube  is  loose  and  pendulous,  over- 
hanging the  ovarium  on  the  back  part  of  the  broad 
ligament. 

The  Fallopian  Tube  seems  to  be  a continuation  of 
the  structure  of  the  uterus,  having  a fibrous  membrane 
externally,  and  an  internal  mucous  one;  the  latter  is 
principally  concerned  in  forming  its  large  extremity, 
and  is  rendered  erectile  in  sexual  excitement,  probably 
by  its  great  vascularity. 

The  Ovaries,  (Ovaria,  Testes  Muliebres,)  are  si- 
tuated one  on  each  side  of  the  uterus,  and  on  the  pos- 


308 


OF  THE  TRUNK. 


terior  face  of  the  broad  ligament  enclosed  in  a dupli- 
cature  of  it.  They  are  compressed  ovoids  about  half 
the  size  of  the  testicle,  of  a very  light  pink  colour; 
are  connected  to  the  uterus  by  a small,  vascular,  and 
fibrous  cord,  called  Ligament  of  the  Ovary,  which  is 
inserted  into  the  uterus  just  below  the  fallopian  tube. 
The  external  end  of  the  ovary  has  one  of  the  processes 
of  the  corpus  fimbriatum  or  morsus  diaboli  adhering  to 
it. 

The  surface  of  the  ovary  is  generally  found  some- 
what uneven,  from  a number  of  marks  resembling  cica- 
trices. It  has  a complete  peritoneal  coat,  and  within 
this  is  another  of  a strong,  compact,  fibrous  character, 
sending  many  processes  internally,  which  corresponds 
with  the  tunica  albuginea. 

The  structure  of  this  body  is  imperfectly  known;  a 
good  deal  of  vascular  fibrous  matter  enters  into  its  com- 
position, containing  from  fifteen  to  twenty  vesicles  of 
various  sizes,  from  the  head  of  a small  pin  to  a French 
pea.  The  parietes  of  these  vesicles  are  very  thin, 
transparent,  and  vascular,  and  contain  an  albuminous 
light  coloured  fluid. 

The  Bladder  and  Rectum,  with  unimportant  excep- 
tions, are  the  same  in  both  sexes.  The  arteries  of  the 
viscera  of  the  pelvis,  in  both  cases,  are  derived  from 
the  internal  iliacs. 

The  Levator  Ani,  Coccygeus,  and  Sphincter  Ain 
muscles  have  the  same  arrangement  as  in  males. 


FEMALE  MAMM^. 


309 


The  Fasciae  connecting  the  bladder  to  the  sides  of 
the  pelvis,  and  the  triangular  ligament  of  the  urethra 
also  exist. 


Section  II. 

Of  the  Female  Mammx. 

The  Mammae  are  two  glandular  bodies,  situated  over 
the  thorax,  upon  the  great  pectoral  muscles  between 
the  arm-pits  and  the  sternum,  and  intended,  in  the 
female,  for  the  secretion  of  milk.  They  are  hemis- 
pherical, and  vary  very  much  in  size,  according  to  the 
age  of  the  person  and  the  state  of  the  uterine  system. 

The  skin  which  covers  the  mamma  is  very  fine  and 
thin,  and  through  it  may  be  seen  readily  the  veins 
which  creep  beneath  it.  It  is  very  extensible,  but 
does  not  possess  much  power  of  contraction.  Beneath 
the  skin,  between  it  and  the  surface  of  the  gland,  there 
is  an  abundance  of  cellular  substance  intermixed  with 
lobules  of  fat,  which  together  make  a greater  volume  of 
matter  than  the  gland  itself.  The  exterior  surface  of 
the  gland  is  rendered  very  unequal,  by  being  penetrat- 
ed at  different  depths  by  this  cellular  and  adipose  mat- 
ter, and  its  lobules  are  divided  by  irregular  fossse  from 
each  other.  The  substance  of  the  gland  is  united  to 


310 


OF  THE  TRUNK. 


the  pectoralis  major  muscle,  by  a loose  cellular  tissue, 
which  contains  very  little  fat. 

The  mamma  is  composed  of  lobes  of  different  sizes, 
united  together  in  such  a way  by  cellular  texture,  that 
they  cannot  be  separated  without  injury  to  them. 
These  lobes  are  composed  of  Lobuli,  which  again  are 
formed  by  granuli  of  a white  colour  tinged  with  red. 
These  granuli  are  the  size  of  a millet-seed,  and,  ac- 
cording to  some  anatomists,  consist  of  vesicles  which 
are  very  apparent  by  the  aid  of  a microscope,  in  a gland 
iilled  with  milk.* 

The  roots  of  the  excretory  vessels,  or  the  lactiferous 
ducts,  arise  from  these  grains;  they  are  extremely  fine, 
and  unite,  after  a short  course,  to  contiguous  ones,  by 
successive  accumulations  resembling  the  branches  of  a 
tree;  large  trunks  are  finally  formed  which  terminate 
in  a sinus,  placed  in  the  centre  of  the  gland  near  the 
base  of  the  nipple.  The  lactiferous  ducts  converge 
from  the  circumference  of  the  gland  to  its  centre;  their 
course,  however,  is  very  tortuous,  and  their  coats  are 
thin,  semitransparent,  and  very  capable  of  extension 
and  contraction.  They  are  mimerous,  from  two  to  four 
of  them  unite  into  a common  root,  called  sinus,  which 
is  only  a few  lines  long,  and  placed  near  the  base  of  the 
nipple.  These  sinuses  are  about  fifteen  in  number,  and 
are  of  different  diameters,  the  largest  about  three  lines 
wide,  but  others  scarcely  exceed  the  diameter  of  tin 

* See  Marjolin,  vol.  ii.  p.  C95- 


FEMALE  MAMMiE. 


311 


factiferous  tubes.  From  the  external  extremity  pf  each 
sinus  arises  a small  excretory  duct,  which  conducts  the 
milk  to  the  surface  of  the  nipple.  This  duct  is  of  a 
conical  shape,  sometimes  dilated  in  its  middle,  and  is 
curved  and  folded  upon  itself  w^hen  the  nipple  is  not 
ill  a state  of  erection,  by  which  means  the  milk  is 
prevented  from  flowing  through  it.  The.  sinuses, 

and  the  excretory  ducts,  are  united  to  each  other  by 
condensed  cellular  membrane;  they  have  no  valves, 
neither  have  the  lactiferous  tubes  in  any  part  of  their 
course. 

An  opinion  was  entertained  by  Haller,  and  by  many 
other  anatomists  after  him,  that  some  of  the  lactiferous 
ducts  originated  in  the  surrounding  cellular  texture; 
this  has  been  refuted  by  the  researches  of  Cuboli.  The 
excretory  ducts  of  the  different  lobes  are,  for  the  most 
part,  kept  distinct  from  each  other,  there  being  no 
anastomoses  between  them;  hence  it  happens  that  in 
the  injection  of  the  gland  with  mercury,  it  is  necessary 
to  inject  each  lactiferous  sinus  separately.  Some  ana- 
tomists have  thought  that  there  is  a direct  communica- 
tion between  the  roots  of  the  lactiferous  tubes,  and  the 
arteries,  veins  and  lymphatics.  Mascagni,  after  a very 
successful  injection  of  the  gland,  in  which  he  filled  its 
vesicles  with  quicksilver,  not  meeting  with  such  an 
occurrence,  was  induced  to  think  that  when  such  com- 
munication did  happen  it  was  by  rupture. 

The  Areola  in  virgins,  is  a rose-coloured  circle. 


312 


OF  THE  TRUNK. 


which  surrounds  the  base  of  the  papilla  or  nipple.  In 
women  who  have  borne  children,  or  in  those  whose 
age  is  advanced,  it  becomes  of  a dark  browm.  The  skin 
of  the  areola  is  extremely  delicate,  and  on  its  surface, 
particularly  in  pregnant  or  nursing  females,  there  are 
from  four  to  ten  tubercles,  which  sometimes  form  a 
regular  circle  near  its  circumference,  and  in  other 
subjects  are  irregularly  distributed.  Each  of  these 
tubercles  has,  near  its  summit,  three  or  four  foramina, 
which  are  the  orifices  of  the  excretory  ducts  of  a little 
gland  forming  the  tubercle.  From  this  gland  is  secreted, 
according  to  some,  an  unctuous  fluid  for  protecting  the 
surface  of  the  areola,  while  others  consider  them  only 
as  lactescent.  The  areola  consists  of  a spongy  tissue, 
beneath  which  there  is  no  fat;  it  is  susceptible  of  dis- 
tention during  lactation,  or  from  sexual  excite- 
ment. 

The  Papilla  is  a truncated  cone  in  the  centre  of 
the  mamma,  of  the  same  colour  with  the  areola,  and 
surrounded  by  it.  The  lactiferous  ducts  terminate 
on  its  extremity.  It  is  collapsed  and  in  a very  pliable 
state  for  the  most  part,  but  when  excited  it  swells, 
becomes  more  prominent,  and  of  a deeper  colour. 
Its  skin  is  rough,  and  provided  with  numerous  and 
very  small  papillse.  Its  internal  structure  consists  of 
the  lactiferous  ducts,  united  by  condensed  cellular 
membrane. 


FEMALE  MAMM^. 


313 


The  mamma  is  supplied  with  blood  from  the  exter- 
nal thoracic,  intercostal,  and  internal  mammary  arteries. 
Its  veins  attend  their  respective  arteries.  The  nerves 
come  from  the  brachial  plexus  and  the  intercostals. 
Its  lymphatics  run  into  the  internal  mammary  and 
axillary  trunks. 


H r 


PART  II. 


CHAPTER  V. 

Of  the  J\'erves  and  Vessels  of  the  Trunk. 

I HAVE  thought  it  better  to  give  a separate  consi- 
deration to  the  nerves  and  vessels  of  the  trunk,  by  not 
involving  them  with  the  viscera;  because  it  is  the 
easiest  manner  of  studying  them,  and  such  as  the  stu- 
dent most  frequently  adopts  when  left  to  his  own  dis- 
cretion; which  alone,  is  in  some  measure,  a proof  of  its 
being  the  most  natural  and  agreeable  method.  The 
/ arteries  should  be  filled  with  either  of  the  coarse  in- 

jections; it  is  less  important  for  the  veins,  and  may  be 
dispensed  with. 


Section  I. 

Of  the  JVei'ves. 

The  Phrenic  Nerve  passes  into  the  thorax  from  the 
neck,  by  the  side  of  the  descending  cava  on  the  right, 
between  it  and  the  pleura;  it  then  continues  on  the 


NERVES. 


315 


side  of  the  pericardium  in  a direction  almost  straight,  to 
the  diaphragm,  going  before  the  root  of  the  lungs.  On 
the  left  side,  with  the  exception  of  the  descending 
cava,  and  of  its  being  turned  somewhat  out  of  its  way  by 
the  projection  of  the  point  of  the  heart,  its  course  is 
the  same.^ 

The  nerve  getting  to  the  diaphragm  is  spread  out  in 
a radiated  direction  on  its  muscular  wing,  both  on  its 
upper  and  lower  surface.  Anatomists  of  sufficient  res- 
pectability report  branches  from  the  sympathetic 
mounting  up  to  the  diaphragm,  and  having  their  ter- 
minating ramifications  united  with  those  of  the  phrenic. 
Portions  of  the  renal  plexus  of  nerves,  are  also  said  to 
be  bestowed  on  the  diaphragm. 

The  Par  Vagum,  before  it  gives  off  the  recurrent 
nerve,  sends  off  one  or  more  twigs  to  join  the  cardiac 
plexus,  it  also  contributes  to  the  same  when  the  recur- 
rent nerve  is  separating  from  it’.  From  a little  below 
this  place,  the  par  vagum  sends  off  the  Anterior  Pulmo- 
nary Plexus,  derived  principally  from  two  branches,  a 
large  and  a small  one,  which  subdivide  and  go  in  front 
of  the  trachea  and  >of  the  root  of  the  lungs.  The  rami- 
fications of  this  plexus  follow  generally  the  bronchium 
and  blood-vessels,  into  the  substance  of  the  lungs,  but 
some  of  them  are  turned  into  the  cardiac  plexus. 

The  trunk  of  the  par  vagum  proceeds  then  on  the  out- 

•*  For  a fui'ther  account  of  this  nerve  see  the  Neck- 


OF  THE  TRUNK. 


316^* 

side  of  thebronchium,  and  a little  lower  down  behind  it, 
then  passes  in  contact  with  the  posterior  surface  of  the 
root  of  the  lungs.  Here  it  gives  off  successively  live 
or  six  branches  of  different  magnitudes,  which  leave 
the  main  trunk  almost  at  right  angles,  divide  and  subdi- 
vide, and  following  the  bronchium,  are  spent  upon  its 
ultimate  ramifications  in  the  lungs.  These  branches 
constitute  the  Posterior  Pulmonary  Plexus. 

After  the  posterior  pulmonary  plexus  is  given  oil’, 
the  par  vagum  remaining  still  considerable,  betakes  it- 
self to  the  oesophagus,  being  split  into  three  or  four  fas- 
ciculi which  spread  out  and  unite  again.  From  the 
crossing  of  the  bronchium  to  the  joining  with  the  oeso- 
phagus, a great  many  small  ramifications  are  sent  to  the 
oesophagus,  forming  a plexus  on  it;  some  are  sent  also  to 
the  aorta. 

The  Left  Par  Vagum  is  situated  on  the  anterior 
lateral  sui’face  of  the  oesophagus,  and  the  Right  Par 
Vagum  on  the  posterior  lateral  surface,  each  however 
adhering  to  its  own  side,  and  forming  a plexus  which 
partially  surrounds  the  oesophagus.  They  pass  through 
the  foramen  of  the  diaphragm,  along  with  the  oesopha- 
gus, and  their  fibres  are  reassembled  into  more  consi- 
derable trunks.  The  left  par  vagum  is  distributed 
along  the  lesser  curvature  of  the  stomach,  between  the 
cardia  and  the  pylorus,  to  the  anterior  side  of  the  sto- 
mach, to  the  lesser  omentum,  and  some  of  its  branches 
extend  to  the  left  hepatic  and  solar  plexus.  The  right 
par  vagum  surrounds  with  its  branches  the  cardiac  ori 


NERVES. 


317 


fice  of  tlie  stomach,  supplies  the  under  side  and  great 
curvature,  sends  branches  along  the  coronary  artery  to 
unite  to  the  hepatic  and  splenic  plexuses,  and  one  trunk 
to  the  solar  plexus. 

The  Sympathetic,  or  Intercostal  Nerve,  is 
principally  employed  in  the  thorax  in  supplying  the 
heart.  With  this  view  it  sends  to  it  three  nerves  on 
the  right  side,  and  two  on  the  left,  called  Cardiac. 

The  Right  Superior  Cardiac  is  derived  by  several 
filaments  from  tlie  upper  cervical  ganglion,  joined  by 
some  from  the  superior  laryngeal  nerve.  They  unite 
into  one  trunk,  which  accompanies  the  common  carotid 
on  its  external  surface  as  far  as  the  middle  cervical  gan- 
glion; here  the  trunk  divides,  one  part  of  it  and  the 
smaller,  running  along  the  carotid  and  arteria  innom- 
inata  to  the  aorta,  the  other  joining  a plexus  just  below 
the  middle  cervical  ganglion. 

The  Middle  or  Great  Cardiac  Nerve  arises  from  the 
inferior  part  of  the  middle  cervical  ganglion,  passes 
along  the  external  surface  of  the  carotid  artery,  and 
crosses  the  subclavian  in  front  just  at  its  root,  it  then 
goes  along  with  the  arteria  innominata  for  a little  dis- 
tance, and  te.rminates  in  the  upper  part  of  the  cardiac 
plexus. 

The  Third  or  Small  Cardiac  Nerve  comes  from  the 
lower  cervical  ganglion,  by  several  filaments  which 
unite  into  a smaller  number  to  form  a plexus,  which  de- 
scei>ds  behind  the  subclavian  artery,  and  between  the 


318 


OF  THE  TRUNK. 


innominata  and  trachea,  to  the  posterior  part  of  the 
arch  of  the  aorta. 

On  the  left  side  the  Upper  Cardiac  nerve  originates 
in  the  same  way  as  on  the  right,  from  the  first  cervi- 
cal ganglion  and  upper  laryngeal;  attending  the  com- 
mon carotid,  it  is  increased  by  fibrillsB  from  the  sym- 
pathetic, between  the  first  and  second  ganglions.  In 
the  upper  part  of  the  thorax  this  nerve  is  between  the 
carotid  and  subclavian  arteries,  and  at  their  roots  some 
of  its  branches  go  in  front  of  the  aorta  and  others  be- 
hind it.  The  second  cardiac  nerve  of  the  left  side,  is 
derived  from  the  middle  and  lower  cervical  ganglions 
of  the  sympathetic.  Several  branches  being  despatch- 
ed by  the  two  ganglions,  they  form  a plexus  which  sur- 
rounds the  subclavian  at  the  origin  of  the  inferior  thy- 
roid and  transversalis  colli  arteries.  From  this  plexus 
several  cords  proceed  longitudinally  behind  and  before 
the  subclavian  artery  to  the  aorta,  and  here  being  join- 
ed to  branches  from  the  upper  cardiac  nerve,  they 
form  a plexus  on  the  anterior  and  posterior  faces  of  the 
aorta. 

The  Cardiac  Plexus  consists  of  a very  considerable 
number  of  nervous  filaments,  formed  by  the  combina- 
tion of  the  cardiac  nerves  on  both  sides,  with  branches 
sent  off  from  the  recurrent  nerves- and  the  par  vagum. 
It  is  placed  between  the  aorta  and  the  trachea  and 
bronchia,  and  extends  from  the  lower  cervical  ganglion 
to  the  top  of  the  base  of  the  heart  where  the  aorta  and 
pulmonary  artery  come  out.  It  is  fixed  in  loose  cel 


NERVES. 


819 


lular  and  adipose  membrane  at  its  upper  part;  below,  its 
meshes  are  much  involved  with  the  glands  about  the 
bifurcation  of  the  trachea,  and  on  the  aorta  its  branches 
lie  very  close  to  this  vessel,  being  bound  to  it  by  the 
internal  lamina  of  the  pericardium. 

Several  branches  of  the  plexus  wind  over  to  the  front 
of  the  aorta  and  pulmonary  artery,  where  they  are  also 
conlined  closely  to  these  vessels  by  the  internal  lamina 
of  the  pericardium,  and  seen  to  enter  into  their  struc- 
ture. The  cardiac  plexus,  penetrating  from  the  base 
of  the  heart  to  the  root  of  the  aorta,  is  diffused  through 
the  muscular  structure  of  the  former,  its  trunks  follow- 
ing the  courses  of  the  coronary  arteries. 

The  Sympathetic  Nerve,  from  the  last  cervical 
ganglion,  proceeds  over  the  head  of  the  first  rib,  and 
descends  through  the  thorax  in  contact  with  the  heads 
of  all  the  ribs,  and  exterior  to  the  pleura.  At  the  up- 
per edge,  of  the  head  of  each  rib  it  forms  ar  ganglion, 
which  unites  with  the  intercostal  nerve  behind  it  by 
two  branches.  At  the  lower  part  of  the  thorax  it  pe- 
netrates into  the  abdomen  beneath  the  crus  of  the 
diaphragm;  it  then  proceeds  forwards  and  downwards 
on  the  spine  between  the  tendinous  crus  of  the  dia- 
phragm and  the  psoas  magnus  muscle,  and  lies  on  the 
side  of  the  bodies  of  the  lumbar  vertebrae,  being  near 
the  vena  cava  on  the  right  sidp  and  the  aorta  bn  the 
left.  About  the  middle  of  the  body  of  each  lumbar 
vertebra,  it  forms  a ganglion  which  dismisses  one  or  two 


320 


OF  THE  TRUNK. 


nervous  filaments  to  the  corresponding  lumbar  nervcj 
which  filaments  pass  between  the  bone  and  the  psoas 
muscle.  From  the  loins,  the  sympathetic  descends  in- 
to the  pelvis  on  the  inner  side  of  the  foramina  of  the 
sacrum;  here  also  it  forms  a ganglion  corresponding 
with  each  sacral  nerve,  and  detaches  a filament  to  join 
it.  Finally  the  sympathetic  terminates  on  the  os  coc- 
cygis  where  the  ultimate  branches  of  the  opposite  sides 
unite. 

From  several  of  the  upper  ganglions  of  the  sympa- 
thetic in  the  thorax,  fibrillae  depart  which  join  the 
posterior  pulmonary  plexus,  and  also  are  distributed 
in  the  form  of  a plexus  on  the  aorta.  F rom  the  sixth, 
seventh,  eighth,  ninth,  and  tenth  thoracic  ganglions, 
branches  are  sent  off,  which,  descending  obliquely  on 
the  sides  of  the  vertebrae,  unite  successively  so  as  to 
form  a considerable  trunk,  the  Great  Splanchnic  Nerve, 
which  gets  into  the  abdomen  through  the  foramen  in 
the  diaphragm  for  the  aorta,  or  by  penetrating  the 
crus.  From  the  tenth,  eleventh,  and  twelfth  dorsal 
ganglions,  filaments  are,  in  like  manner,  successively  sent 
off,  which  form  one  or  two  trunks  that  penetrate  into  the 
abdomen  through  the  crus  of  the  diaphragm;  this  con- 
stitutes the  Lesser  Splanchnic  Nerve,  which,  in  part, 
unites  to  the  great  splanchnic  nerve,  and  the  remainder 
goes  to  the  renal  plexus. 

The  Great  Splanchnic  Nerve,  having  entered  the 


NERVES. 


321 


abdomen,  is  associated  with  the  semilunar  ganglion. 
This  ganglion  is  situated  on  the  crus  of  the  diaphragm, 
and  on  the  sides  of  the  coeliac  and  superior  mesen- 
teric arteries.  It  is  frequently  formed  rather  by  a 
congeries  of  small  ganglions  arranged  in  a lunated  form, 
than  by  a single  one.  These  small  ganglions  are  united 
by  a reticular  work  of  nerves,  and  from  them  proceeds 
a very  intricate  and  combined  net-work  of  nervous 
fibres,  called  the  Solar  Plexus. 

The  Solar  Plexus  is  behind  the  stomach  and  above 
the  pancreas,  and  surrounds  with  its  branches,  the 
coeliac,  superior  mesenteric,  and  renal  arteries.  It  is 
formed  from  the  semilunar  ganglions  of  both  sides,  and 
to  their  ramifications  are  added  some  from  the  par  va- 
gum  and  phrenic  nerves.  That  portion  of  the  solar 
plexus  on  the  coeliac  artery,  assumes  the  name  of  coeliac, 
and  dismisses  ramifications  in  the  coui'se  of  the  gastric, 
hepatic,  and  splenic  arteries  to  the  viscera  supplied 
by  them,  as  the  stomach,  liver,  pancreas,  and  spleen. 

The  Superior  Mesenteric  Artery  has  around  it  the 
Superior  Mesenteric  Plexus,  which  accompanies  the 
arterial  branches  to  the  right  side  of  the  colon,  to  its 
transverse  portion,  and  to  all  the  small  intestines. 
From  the  inferior  part  of  this  plexus,  proceeds  a de- 
tachment in  front  of  the  aorta,  to  the  inferior  mesente- 
ric artery  which  supplies  the  left  side  of  the  colon  and 
the  rectum. 


322 


OF  THE  TRUNK. 


From  the  lower  part  of  the  solar  plexus,  arises  the 
Renal  Plexus,  which  surrounds  the  emulgent  arteiy, 
and  is  distributed  to  the  kidney  and  to  the  capsula 
renalis.  The  renal  plexus  detaches  near  the  kidney  a 
few  fibres,  which,  being  joined  by  others  from  the  first 
or  second  lumbar  nerves,  accompany  the  spermatic 
artery,  and  are  therefore  called  the  Spermatic  Plexus. 
In  the  male  they  are  distributed  on  the  cord  arid  testis, 
and  in  the  female  on  the  ovarium  and  fallopian  tube. 

From  the  lower  part  of  the  renal  and  solar  plexus, 
there  proceeds  a reticulated  structure  of  nerves  in 
front  of  the  aorta,  as  low  down  as  its  bifurcation.  This 
is  joined  by 'fibres  on  each  side  from  the  sympathetic 
of  the  loins.  It  divides,  and  following  the  course  of 
the  hypogastric  artery  on  each  side,  is  distributed  to 
the  bladder,  rectum,  and  vesiculae  seminales  of  the 
male,  and  to  the  uterus,  vagina,  bladder,  and  rectum 
of  females.  This  is  the  Hypogastric  Plexus,  which  is 
further  increased  by  filaments  from  the  sacral  parts  of 
the  sympathetic. 

The  other  nerves  of  the  trunk  consist  of  the  Dorsal, 
the  Lumbar,  and  the  Sacral.  Each  arises  as  a solitary 
trunk  from  its  appropriate  spinal  ganglion,  and  very 
soon  divides  into  anterior  and  posterior  fasciculi.  The 
posterior  is  distributed  to  the  muscles  of  the  back,  but 
the  anterior  has  a destination  not  so  uniform.  ‘ 

The  anterior  branches  of  the  Dorsal  nerves  are  all 
connected  to  the  ganglions  of  the  sympathetic,  and. 


ARTERIES. 


323 


running  between  the  internal  and  external  intercostal 
muscles,  are  distributed  to  the  parietes  of  the  thorax 
and  abdomen.  'The  first  dorsal  nerve  joins  the  axil- 
lary plexus.  The  second  sends  a branch  through 
the  external  intercostal  muscle  to  the  axilla,  which  joins 
with  a branch  of  the  internal  cutaneous  nerve  of  the 
arm,  and  is  supposed,  as  it  also  sends  a filament  to  the 
lower  cervical  ganglion  of  the  sympathetic,  to  estab- 
lish the  sympathy  between  the  arm  and  the  heart  in 
angina  pectoris.  The  third  dorsal  also  sends  a branch 
to  the  axilla. 

The  upper  lumbar  nerves  are  employed  upon  the 
integuments  of  the  abdomen,  and  in  the  formation  of 
the  lumbar  plexus  which  supplies  the  front  of  the  thigh 
and  leg.  The  lower  lumbar  nerves  and  the  sacral, 
form  the  sciatic  plexus,  which  supplies  the  posterior 
parts  of  the  lower  extremity. 

The  further  consideration,  of  the  spinal  nerves  is 
referred  to  the  Anatomy  of  the  Limbs. 


Section  II. 

Of  the  Blood-vessels  of  the  Trunk. 

The  course  of  the  aorta,  from  its  origin  to  its  passage 
through  the  diaphragm,  has  already  been  mentioned, 
(see  Thorax;)  as  well  as  that  a line  to  subtend  the  base 


324 


OF  THE  TRUNK. 


of  its  curvature,  must  be  drawn  from  the  sternal  extre- 
mity of  the  third  rib  on  the  right,  to  the  dorsal  extre- 
mity of  the  third  rib  on  the  left  side.  The  first 
branches  given  off  after  the  coronary  arteries,  are  the 
Arteria  Innominata,  the  Left  Carotid,  and  the  Left 
Subclavian.  The  Arteria  Innominata  is  in  advance 
of  the  others,  and  divides,  after  an  inch  and  a quarter 
of  length,  into  right  carotid  and  subclavian.  For  an 
exposition  of  the  course  of  the  Carotids,  see  the  article 
Neck. 

The  Subclavian  Artery,  before  it  passes  between 
the  scaleni  muscles,  sends  off  five  branches:  the  Inferior 
Thyroid,  the  Vertebral,  and  the  Transverse  Artery  of 
the  neck  have  been  mentioned  in  the  article  Neck; 
the  other  two  belong  to  the  trunk.  The  first  is  the 
Arteria  Mammaria  Interna,  which  comes  from  the 
subclavian  commonly  before  any  of  the  others:  and  the 
second  is  the  Superior  Intercostal  Artery,  about  the 
last  of  the  cluster. 

The  Internal  Mammary  Artery,  after  its  origin, 
descends  immediately,  and  fixes  itself  between  the 
pleura  and  the  cartilages  of  the  true  ribs,  about  tliree- 
fourths  of  an  inch  from  the  outer  edge  of  the  sternum; 
it  gets  into  the  abdomen  and  is  distributed  finally  to 
the  rectus  muscle,  anastomosing  in  it  with  the  epigas- 
tric artery.  It  sends  a branch  which  attends  the 
phrenic  nerve  on  the  side  of  the  pericardium;  it  sup- 
plies the  intercostal  muscles,  anastomoses  with  the 
intercostal  arteries,  and  sends  some  branches  to  the 


mamma. 


ARTERIES. 


325  . 


The  Superior  Intercostal  Artery  runs  across  the 
heads  of  the  first  and  second  ribs,  and  supplies  the  in- 
tercostal spaces  corresponding  to  them;  it  also,  some- 
times, supplies  the  third  intercostal  space. 

Below  its  curvature,  in  the  thorax,  the  aorta  gives 
off  the  CEsophageal,  the  Bronchial,  the  Posterior  Me- 
diastinal and  the  Intercostal  Arteries. 

The  Bronchial  Arteries  are  vessels  intended  for 
the  nourishment  of  the  lungs;  the  right  comes  from  the 
superior  intercostal  artery,  and  the  left  from  the  aorta; 
this  arrangement  is  not  uniform,  forsometimes  both  come 
from  the  aorta. 

The  CEsophageal  Arteries  are  five  or  six  in  number, 
and  are  spent  upon  the  cesophagus,  as  their  name  im- 
plies; the  lowermost  descends  to  the  stomach. 

The  Posterior  Mediastinal,  as  their  name  indicates, 
supplies  the  posterior  mediastinum  and  its  contents. 

The  Aortic  Intercostals  supply,  commonly,  the  ten 
inferior  intercostal  spaces.  The  upper  ones  have  to 
rise  somewhat  obliquely  to  get  to  their  destination, 
whereas  the  lower  ones  pass  nearly  horizontally.  The 
right  are  longer  than  the  left,  and  the  oesophagus  is  in 
front  of  them.  Each  one  joins  the  rib  near  its  tuber- 
cle, and  keeps  at  its  lower  edge,  between  the  internal 
and  external  intercostal  muscles  in  the  groove  of  the 
bone.  The  first  branch  is  the  dorsal,  given  off  near 
the  spine,  which  passes  to  the  muscles  of  the  back,  and 


326 


OF  THE  TRUNK. 


despatches  an  arteriole  through  the  intervertebral 
foramen  to  the  medulla  spinalis.  When  the  intercostal 
arrives  near  the  middle  of  the  rib,  it  sends  off  a branch, 
which  passes  near  the  upper  edge  of  the  lower  rib. 
When  it  has  got  two-thirds  of  the  length  of  the  rib,  it 
leaves  the  lower  edge  to  be  distributed  to  the  inter- 
costal space  and  contiguous  parts. 

The  Abdominal  Aorta  passes  almost  in  front  of  the 
vertebrae,  being  pushed  but  very  little  to  the  left  of 
the  median  line.  It  gives  off  several  large  branches 
to  the  viscera,  and  at  the  intervertebral  space  of  the 
fourth  and  fifth  vertebrae  of  the  loins  it  divides  into  the 
two  Primitive  Iliacs. 

The  Phrenic  Arteries  come  from  the  aorta  imme- 
diately on  the  latter  emerging  between  the  crura  of 
the  diaphragm.  They  are  two  in  number,  and  named 
from  their  situations.  Right  and  Left;  they  ramify  on 
the  concave  surface  of  the  diaphragm.  Their  origin 
is  subject  to  variations. 

The  Cceliac  Artery,  (Arteria  Cceliaca)is  immediate- 
ly below  the  phrenic;  it  is  a large  vessel  about  half  an 
inch  long,  standing  from  the  aorta  at  right  angles,  and 
divides  into  the  Hepatic,  Gastric  or  Coronary,  and 
Splenic  Arteries. 

The  Hepatic  Artery  goes  to  the  liver  through  the 


ARTERIES. 


327 


capsule  of  Glissoiij  and  is  distributed  through  this  vis- 
cus.  Near  the  liver  it  sends  off  the  Arteria  Gastrica 
Dextra,  which  is  distributed  to  the  great  curvature  of 
the  stomach  and  the  contiguous  parts. 

The  Gastric  Artery  is  between  the  other  two;  it 
joins  the  stomach  near  the  cardia,  and  proceeds  along 
the  lessure  curvature  to  the  pylorus,  supplying  conti- 
guous parts. 

The  Splenic  Artery,  is  the  largest  of  the  three. 
It  goes  tortuously  along  the  upper  edge  of  the  pancreas 
to  the  spleen;  in  its  course  it  sends  to  the  stomach  the 
Gastrica  Inferior  Sinistra,  which  is  spent  on  its  greater 
extremity  and  the  left  side  of  the  greater  curvature. 
From  this  vessel  also  are  derived  the  Vasa  Brevia  of 
the  stomach,  and  the  Arteries  of  the  Pancreas. 

The  Superior  Mesenteric,  (Arteria  Mesenterica 
Superior)  is  about  half  an  inch  below  the  coeliac,  and  is 
nearly  of  the  same  size;  it  passes  downwards  under  the 
pancreas  and  above  the  duodenum,  supplying  all  the 
small  intestines,  the  right  side  of  the  colon,  and  its 
transverse  arch.  It  has  a great  many  anastomoses  in 
it,  constituted  by  a series  of  arcades,  one  upon  the 
other,  diminishing  in  size  as  they  approach  the  intes- 
tine. That  portion  of  the  artery  which  supplies  the 
junction  of  the  ileum  with  the  colon,  is  called  Arteria 
Ileo-Colica;  that  which  supplies  the  right  side  of  the 
great  intestine,  is  the  Arteria  Colica  Dextra;  and  that 


328 


OF  THE  TRUNK. 


which  supplies  the  arch  of  the  colon,  is  the  Coliea 
Media.  • 

The  Emulgent  Arteries,  (Arterise  Emulgentes)  are 
two  in  number,  one  from  each  side  of  the  aorta,  coming 
off  at  right  angles  from  it,  and  not  much  inferior  in 
size  to  the  mesenteric.  The  right  is  the  longest,  and 
passes  behind  the  ascending  vena  cava.  They  go  to 
the  kidneys  and  to  the  capsulse  renales.  The  arterial 
distribution  from  the  aorta  here  is  subject  to  varia- 
tions, the  arteries  of  the  capsulge  renales  coming  some- 
times from  the  aorta,  and  on  other  occasions  from  the 
emulgents.  There  are  also  several  arteries  going  to 
the  adipose  matter  in  which  the  kidneys  are  placed, 
equally  unsettled  in  their  origin. 

The  Spermatic  Arteries,  (Arteriae  Spermaticae) 
arise  immediately  below  the  emulgents,  one  on  each 
side;  they  are  about  the  size  of  a crow-quill,  and  are 
remarkable  for  their  length;  sometimes  the  left  arises 
from  the  emulgent  of  that  side.  They  pass  downwards 
to  the  testicles,  behind  the  peritoneum,  and  before  the 
psosB  muscles,  not  far  from  the  ureters,  spermatic  plex- 
us of  nerves,  and  spermatic  veins.  At  the  internal 
abdominal  ring  they  meet  with  the  vasa  deferentia, 
and  constituting  a part  of  the  spermatic  cords,  are  dis- 
tributed on  the  testicles,  in  the  manner  described  in 
the  account  of  these  organs.  In  the  female,  these 
arteries  go  to  the  ovaria,  fallopian  tubes,  and  uterus. 


ARTERIES. 


329 


The  Inferior  Mesenteric,  (Arteria  Mesenterica  In- 
ferior) arises  below  the  spermatics;  it  is  much  smaller 
than  the  superior.  Three  branches  proceed  from  it, 
called  the  Left  Colic  Arteries,  from  their  distribution 
to  the  left  side  of  the  colon,  and  are  distinguished  from 
each  other  by  the  terms  Superior,  Middle,  and  Infe- 
rior. The  superior  anastomoses  with  the  colica  media^ 
forming  with  it  the  great  Mesocolic  Arch.  The 
others  supply  the  sigmoid  flexure  of  the  colon,  and  the 
part  just  above  it.  A branch  is  continued  from  the 
inferior  mesenteric  to  the  rectum,  constituting  the 
superior  hemorrhoidal  artery. 

From  the  centre  of  the  fork  formed  by  the  bifur- 
cation of  the  aorta,  there  proceeds  a small  arterial 
tube,  about  the  size  of  a crow-quill,  called  the  Arteria 
Sacra  Media,  from  its  running  down  to  the  os  coc- 
cygis,  just  over  the  middle  line  of  the  sacrum.  It 
sends  branches  on  either  side  towards  the  foramina  in 
the  sacrum. 

The  Lumbar  Arteries,  (Arterise  Lumbares)  are  from 
three  to  five  in  number  on  either  side;  they  pass  off  at 
right  angles  from  the  aorta  over  the  sides  of  the  lumbar 
vertebrae,  some  of  their  branches  penetrate  the  interver- 
tebral foramina  to  get  to  the  medulla  spinalis,  others  pass 
to  the  muscles  of  the  back.  Besides  which,  the  lower 
parts  of  the  parietes  of  the  abdomen  are  supplied  by 

T t 


330 


OF  THE  TRUNK. 


them.  They  inosculate  with  the  circiimflexa  ilii,  with 
the  epigastric  and  with  the  gluteal  arteries. 

The  Primitive  Iliacs,  (Art.  Iliacae  Communes,)  one 
on  each  side,  are  formed  by  the  termination  of  the 
abdominal  aorta ; they  extend  from  the  fourth  lumbar 
vertebra  to  the  sacro-iliac  junction,  opposite  to  which 
they  divide  into  two  trunks,  the  External  Iliac  Artery 
and  the  Hypogastric.  In  this  course  they  give  off  no 
collateral  branch  of  any  consequence,  and  are  crossed 
by  the  ureters. 

The  Hypogastric  or  Internal  Iliac,  (Arteria  Iliaca 
Interna,  or  Ramus  Hypogastricus, ) gives  off  several 
branches,  the  origins  of  which  differ  considerably.  The 
main  trunk  itself  is  of  various  lengths,  and  is  distributed 
to  the  viscera  of  the  pelvis  and  to  the  muscles  on  ite 
external  surface.  Sometimes  it  is  previously  divided 
into  two  principal  trunks,  an  anterior  and  a posterior. 
From  it  the  following  branches  proceed. 

1.  The Ilio-Lumbar  Artery,  (Arteria  Ilio  Lumbalis,) 
is  commonly  the  first  branch  of  the  hypogastric  or  of  its 
posterior  trunk.  Arising  from  its  posterior  external 
part,  it  passes  outwardly  between  the  psoas  magnus  and 
iliacus  internus  muscles,  and  divides  into  two  branches, 
one  of  which  is  distributed  to  the  loins,  and  the  other 
upon  the  iliacus  internus  muscle. 

2.  The  Lateral  Sacral  Arteries,  (Arteriac  Sacrse 
Laterales,)  come  next,  arising  by  one  or  more  tninks 


ARTERIES. 


331 


from  the  hypogastric  or  one  of  its  large  branches;  they 
commonly  equal  in  number  the  foramina  of  the  sacrum, 
and  passing  into  them  are  distributed  upon  the  inferior 
part  of  the  cauda  equina ; they  also  anastomose  with 
the  middle  sacral  artery. 

3.  The  Obturator  Artery,  (Arteria  Obturatoria, ) 
comes  from  the  hypogastric,  or  one  of  its  trunks,  and 
passes  along  parallel  with  the  brim  of  the  pelvis;  going 
through  the  obturator  foramen  it  is  distributed  to  the 
hip  joint,  and  to  the  muscles  on  the  upper  internal  part 
of  the  thigh.  Its  origin  is  occasionally  from  the  epi- 
gastric. 

4.  The  Middle  Hemorrhoidal  Artery,  (Arteria 
Hemorrhoidea  Media,)  comes  sometimes  from  tjae 
gluteal,  &c.  It  is  thus  named  from  its  relative  position 
to  the  upper  and  lower  hemorrhoidal,  on  the  rectum. 
Besides  going  to  this  organ,  it  supplies  the  prostate 
gland  and  the  vesiculse  seminales  of  the  male,  and  the 
vagina  and  bladder  in  females. 

5.  The  Uterine  Artery,  (Arteria  Uterina,)  is  pecu- 
liar to  females,  and  gets  to  the  uterus  between  the 
laminae  of  the  broad  ligaments. 

6.  The  Vesical  Arteries,  (Arteriae  Vesicales,)  are 
derived  from  what  was  the  umbilical  artery  of  the  foetus, 
and  are  distributed  to  the  bladder. 

What  remains  of  the  hypogastric  consists  in  two  large 
branches,  the  Gluteal  and  the  Ischiatic. 

7.  The  Gluteal  Artery,  (Arteria  Glutaea,)  passes  out 
of  the  pelvis  at  the  upper  part  of  the  ischiatic  foramen 


332 


OF  THE  TRUNK. 


above  the  pyriformis  muscle,  it  is  situated  in  contact 
with  the  edge  of  the  bone,  and  its  trunk  is  accessible 
from  the  external  parts  of  the  pelvis.  Having  got  to 
its  outside,  the  trunk  of  the  gluteal  divides  immedi- 
ately into  two  branches,  which  pass  forwards  towards 
the  anterior  margin  of  the  pelvis,  one  of  them  ramify- 
ing between  the  gluteus  minimus  and  medius,  and  the 
other  between  the  medius  and  maxhnus. 

8.  The  Ischiatic  Artery,  (Arteria  Ischiadica,)  com- 
ing from  the  inferior  part  of  the  hypogastric,  is  situated 
before  the  belly  of  the  pyriformis  muscle,  and  issues 
from  the  pelvis  below  its  inferior  edge  and  in  front  of 
the  sciatic  nerve.  It  pursues  its  course  downwards  on 
the  back  part  of  the  thigh,  between  the  trochanter 
major  and  the  tuberosity  of  the  ischium,  being  then  at 
the  internal  edge  of  the  sciatic  nerve.  In  the  pelvis 
it  sends  off  the  Internal  Pudic,  and  on  the  outside 
of  it,  is  distributed  to  the  inferior  edge  of  the  gluteus 
maximus,  and  to  the  muscular  structure  near  the  sa- 
crum and  coccyx ; also  to  the  muscles,  on  the  back  and 
upper  parts  of  the  thigh. 

The  Internal  Pudic  Artery,  (Arteria  Pudica  In- 
terna,) emerges  from  the  pelvis  with  the  ischiatic,  and 
then  returns  between  the  two  sacro-sciatic  ligaments  tc 
the  inner  side  of  the  tuberosity  of  the  ischium,  and  con- 
tinues on  the  inner  side  of  the  rami  of  the  ischium  and 
pubes  towards  the  symphysis.  In  this  coui*se  it  gives  off 


ARTERIES. 


333 


several  branches  in  the  following  order.  The  Lower 
Hemorrhoidal  Artery  to  the  pyriformis  muscle  at  its 
lower  edge,  to  the  lower  part  of  the  rectum,  and  to  the 
sphincter  ani  muscle.  To  the  back  part  of  the  scrotum,  be- 
tween the  transversusperinei  muscle  and  tlie  skin  it  gives 
the  Perineal  Artery,  originating  near  this  muscle  and 
passing  in  its  direction.  Upon  the  arrival  of  the  inter- 
nal pubic  near  the  penis,  it  detaches  to  this  body  a 
branch  which  penetrates  and  ramifies  minutely  through 
the  structure  of  the  corpus  spongiosum  urethrae.  At  the 
symphysis  of  the  pubes  it  sends  off  a branch  which  gets 
to  the  dorsum  of  the  penis,  and  extends  longitudinally 
as  far  as  the  glans,  being  distributed  to  the  elastic  liga- 
ment, to  the  integuments,  and  to  the  prepuce;  this  is  the 
Superficialis  Dorsi  Penis.  Finally,  the  terminating 
branch  of  the  internal  pudic  penetrates  into  the  corpus 
cavernosura,  passes  straight  forwards  on  the  septum,  and 
is  distributed  to  the,  cells,  by  very  minute  branches, 
some  of  which  go  to  the  other  side. 

The  External  Iliac  Artery,  (Arteria  Iliaca  Externa, ) 
seems  to  be  the  continuation  of  the  common  iliac  ; it 
passes  along  the  brim  of  the  pelvis  on  the  inner  side  of 
the  psoas  magnus  muscle  to  Poupart’s  Ligament.  Here 
it  is  about  half  way  between  the  symphysis  of  the  pubes 
and  the  anterior  superior  spinous  process  of  the  ilium, 
having  the  anterior  crural  nerve  on  its  outside  and  the 
internal  iliac  vein  on  its  inside.  It  gives  off  no  bran- 


I 


334  OF  THE  TRUNK. 

ches  till  it  reaches  Poupart’s  ligament,  when  the  Epi- 
gastric arises  from  it. 

The  Epigastric  Artery,  (Arteria  Epigastrica, ) at 
first  passes  inwards ; it  then  rises  upwards  obliquely 
till  it  reaches  the  exterior  edge  of  the  rectus  muscle. 
Continuing  afterwards  to  ascend,  it  is  spent  upon  the 
anterior  parietes  of  the  abdomen  by  many  branches, 
some  of  which  inosculate  with  the  internal  mammary. 

The  Circumflex  Artery,  (Arteria  Circumflexa  Ilii,) 
arises  from  the  external  iliac  opposite  to  the  epigastric. 
It  runs  along  the  posterior  edge  of  Poupart’s  ligament 
to  the  spinous  process  of  the  ilium ; thence  it  continues 
its  course  near  the  internal  margin  of  the  crista,  being 
distributed  to  the  iliacus  internus  muscle.  A branch 
of  it,  near  the  spinous  process,  rises  upwards  and  is 
spent  upon  the  abdominal  muscles.  It  anastomoses  with 
the  arteria  ilio  lumbalis. 

Veins  of  the  Trunk. 

The  Superior  Cava,  (Cava  Descendens,)  is  suffici- 
ently alluded  to  in  the  description  of  the  thorax,  to 
render  a minute  notice  of  it  here  unnecessary.  It  re- 
ceives the  blood  from  the  left  arm  and  side  of  the  head 
by  a trunk  (the  vena  innomiuata,)  common  to  the  two, 
which  crosses  the  sternum  obliquely  a little  below  its  su- 
perior edge.  This  venous  trunk,  and  the  one  belong- 
ing to  the  right  arm  and  the  right  side  of  the  head, 
constitute  the  Descending  Cava,  properly  speaking. 


VEINS, 


335 


On  a horizontal  line  with  the  upper  edge  of  the  root 
of  the  right  lung  is  the  point  where  the  descending 
cava  is  joined  by  the  vena  azygos.  The  latter  is  form- 
ed hy  the  union,  into  one  trunk  successively,  of  the  ten 
inferior  intercostal  veins  of  the  right  side.  About  the 
sixth  dorsal  vertebra  this  trunk  is  joined  by  one  form- 
ed by  the  successive  union  of  the  six  inferior  intercostal 
veins  of  the  left  side.  The  trunk  of  the  vena  azygos, 
as  stated,  is  on  the  right  side  of  the  posterior  medi- 
astinum, and  forms  a regular  and  beautiful  arch  over 
the  root  of  the  right  lung. 

The  Superior  Intercostal  Veins  of  the  left,  discharge 
into  the  subclavian  vein  by  a common  trunk ; the  two 
superior  of  the  right  side  into  the  descending  cava. 

The  Internal  Mammary  Vein  has  nothing  very  pe- 
culiar; it  observes  the  course  of  its  artery,  and  empties 
into  the  subclavian  vein  near  its  origin. 

The  Cava  Ascendens  is  formed  in  the  lower  part  of 
the  trunk,  by  the  union  of  the  external  and  internal 
iliac  veins,  into  the  common  iliacs  and  the  subsequent 
junction  of  the  latter  at  the  fourth  dorsal  vertebra. 
This  vein  ascends  on  the  right  of  the  aorta,  receives 
many  accessions  in  its  course,  penetrates  the  right  open- 
ing of  the  diaphragm,  and  terminates  in  the  right 
auricle. 

Each  artery  of  the  pelvis  has  its  corresponding  vein; 
it  is  therefore  unnecessary  to  describe  the  latter,  ex- 


336 


OF  THE  TRUNK. 


cept  in  regard  to  peculiarities.  About  the  neck  of  the 
bladder,  vesiculse  seminales,  and  the  base  of  ther  pro- 
state there  is  a considerable  accumulation  of  veins  form- 
ing a very  vascular  plexus  of  them;  they  come  origi- 
nally from  the  vena  ipsius  penis  and  from  the  proper 
vesical  veins. 

The  several  veins  of  the  pelvis  derived  from  the 
ischiatic,  gluteal,  and  internal  pudic  arteries,  &c.  ac- 
cumulate at  the  sacro-iliac  junction  into  one  trunk, 
which  ascends  by  the  side  of  the  hypogastric  artery 
and  joins  the  external  iliac  vein. 

The  ascending  cava  is  joined,  at  its  fork,  by  the 
middle  sacral  vein,  and  above  it,  by  the  lumbar  veins 
on  each  side.  The  right  spermatic  vein  discharges 
into  the  ascending  cava,  but  the  left  into  the  emulgent 
of  that  side.  The  emulgent  and  capsular  veins  corres- 
pond with  the  arteries,  the  right  being  shorter  than 
the  left,  from  the  position  of  the  vena  cava.  The  left 
emulgent  vein  is  in  front  of  the  aorta. 

The  ascending  cava  is  next  joined  by  the  hepatic 
veins  which  have  been  mentioned,  and  lastly,  by  the 
phrenic. 

The  Venous  Trunks,  derived  from  the  superioi’  and 
inferior  mesenteric  arteries  and  from  those  of  the 
coeliac  which  do  not  go  to  the  liver,  as  the  splenic  and 
gastric,  form  the  large  trunk  of  the  vena  portarum.  the 
history  of  which  is  given  in  tlie  account  of  the  liver. 


THORACIC  DUCT. 


337 


Section  III, 

The  Thoracic  Duet,  {Vas  Chy  lifer  us.) 

The  common  trunk  of  the  absorbent  system  com- 
mences most  commonly  at  the  second  or  third  lumbar 
vertebra,  in  front  of  its  body,  by  the  union  of  the 
absorbent  vessels  of  the  lower  extremities,  pelvis,  and 
intestines.  This  vessel,  immediately  after  its  forma- 
tion, is  sometimes  subjected  to  a dilatation  of  various 
shapes  and  lengths,  called  the  Receptaculum  Chyli;  after 
which  it  proceeds  regularly  upwards  in  front  of  the  ver- 
tebrae, between  the  vena  azygos  and  the  aorta,  to  the 
upper  part  of  the  thorax.  It  passes  between  the  crura  of 
the  diaphragm,  and,  for  some  part  of  its  course,  is 
immediately  behind  the  oesophagus.  At  the  fourth 
dorsal  vertebra  it  begins  to  incline  to  the  left,  and, 
preserving  that  direction,  it  gets  into  the  neck  as  high 
as  the  upper  edge  of  the  seventh  cervical  vertebra 
and  just  to  its  left  side.  Here  it  forms  an  arch,  which 
descends  forwards  and  outwards  in  front  of  the  sub- 
clavian artery,  and  between  the  internal  jugular  vein 
and  the  scalenus  anticus  muscle,  and  there  terminates 
by  an  orifice  protected  by  two  valves,  in  the  fork  form- 
ed by  the  junction  of  the  left  internal  jugular  and  sub- 
clavian veins. 

Several  interesting  varieties  occur  in  the  vas  chy- 
liferus;  sometimes  two  trunks  are  formed  originally 


u u 


338 


OF  THE  TRUNK 


on  the  lumbar  vertebrae,  which  run  parallel  with  each 
other,  and  then  unite  at  the  lower  dorsal  vertebra. 
The  thoracic  portion  of  the  duct  varies  in  size  and  con- 
tinuity, being  divided  once  or  oftener,  into  two  trunks, 
which  unite  again,  and  being  also  contracted  at  parti- 
cular points.  The  cervical,  or  terminating  portion  of 
the  duct  is  occasionally  divided  into  two  tubes,  which 
have  separate  orifices. 

There  is  a very  good  plate  in  Caldani,  representing 
the  terminations  of  the  several . lymphatic  trunks  in 
the  region  of  the  neck;  in  this  plate  the  thoracic  duct 
empties,  after  a considerable  dilatation,  into  the  inter- 
nal jugular  vein,  about  an  inch  above  its  junction  with 
the  subclavian;  and  the  lymphatics  of  the  left  side  of 
the  head  and  neck,  form  two  trunks,  which  discharge 
separately,  into  the  convex  side  of  the  Thoracic  duct. 
The  lymphatics  of  the  left  upper  extremity  form  a 
trunk,  whose  orifice  is  in  the  subclavian  vein,  about  an 
inch  below  its  junction  with  the  internal  jugular. 
The  lymphatics  of  the  right  arm,  lung,  right  side  of 
the  neck  and  head,  converge  towards  the  junction  of 
the  right  subclavian  and  internal  jugular  by  four  trunjcs, 
and  then  unite  into  one,  which  discharges  itself  at 
the  posterior  face  of  this  junction.  The  venous  orifice 
of  each  of  these  lymphatic  vessels,  is  secured  from  a 
regurgitation  of  blood  by  one  or  more  valves. 


PART  II. 


CHAPTER  VI. 

Of  the  Muscles  of  the  Back. 

Make  an  incision  through  the  integuments  from  the 
lower  part  of  the  occiput  to  the  os  coccygis,  directly 
over  the  spinous  processes  of  the  vertebrae.  Make  a 
second  incision  from  the  lobe  of  the  ear  to  the  acromion 
process.  Unite  the  upper  ends  of  these  incisions. 
Make  a third  cut  through  the  integuments  from  the 
acromion  process  to  the  posterior  fold  of  the  arm-pitj 
extend  the  latter  downwards  to  the  middle  of  the  crista 
of  the  ilium,  in  a direction  somewhat  curved,  the  con- 
vexity of  the  line  being  backwards.  Lastly,  make  a 
cut  horizontally  from  the  acromion  process  to  the  spine. 

Begin  the  dissection  at  the  last  cut,  and  raise  the 
upper,  and  then  the  lower  flap,  in  the  direction  of  the 
muscular  fibres,  as  they  make  their  appearance.  In 
this  manner  is  exposed  the  two  superficial  broad  mus- 
cles of  the  back,  the  Trapezius  and  the  Latissimus 
Dorsi. 

The  Trapezius  is  a beautiful  broad  muscle,  imme- 
diately under  the  skin,  covering  the  back  parts  of  the 


340 


OF  THE  TRUNK. 


neck  and  thorax,  extending  from  the  bottom  of  the 
latter  to  the  top  of  the  former.  Its  anterior  edge 
above,  is  parallel  with  the  posterior  edge  of  the  sterno 
cleido  mastoideus.  Its  posterior  edge  is  joined  with 
that  of  its  fellow,  and  below,  it  overlaps  the  latissimus 
dorsi  in  part. 

It  arises  from  the  occipital  protuberance,  and  from 
eight  or  ten  lines,  sometimes  more,  of  the  upper  trans- 
verse ridge  of  the  occiput,  by  a tendinous  membrane. 
It  arises  also  from  the  live  superior  spinous  processes 
of  the  neck,  through  the  intervention  of  the  Ligamen- 
tum  Nuchse,  and  tendinous  from  the  two  lower  spinous 
processes  of  the  neck,  and  from  all  of  the  back. 

It  is  inserted  fleshy  into  the  external  third  of  the 
clavicle,  tendinous  and  fleshy  into  the  acromion  pro- 
cess, and  into  all  the  spine  of  the  scapula.  Its  fibres 
having  a very  extended  origin  must  of  course  con- 
verge in  getting  to  these  insertions;  the  upper  fibres 
descend,  the  lower  ascend,  and  the  middle  are  hori- 
zontal. 

It  draws  the  scapula  towards  the  spine.  In  the  cer- 
vical portion  of  these  muscles,  formed  by  the  origins 
of  both  muscles  united,  is  an  elliptical  expanse  of  ten- 
don, lying  over  the  ligamentum  nuchaB,  and  extended 
on  each  side.  The  ligamentum  nuchse  itself,  is  a ver- 
tical septum  of  ligamentous  matter,  extending  from  the 
central  line  of  the  occipital  bone,  to  the  spinous  pro- 
cesses of  all  the  vertebrae  of  the  neck.  At  its  upper 


MUSCLES  OF  THE  BACK. 


341 


part,  where  the  spinous  processes  of  the  neck  are  short, 
this  membrane  is  very  broad,  and  divides  completely 
the  muscles  of  the  two  sides  of  the  neck  from  each 
other. 

The  Latissimus  Dorsi  is  situated  under  the  skin 
at  the  lower  part  of  the  back,  so  as  to  cover  its  whole 
posterior  portion.  It  arises  by  a thin,  tendinous  ex- 
panse, from  the  seven  inferior  spinous  processes  of  the 
back,  and  by  a thick  tendinous  membrane  from  all  the 
spines  of  the  loins  and  sacrum.  This  membrane  is  the 
fascia  lumborum,  is  common  to  several  of  the  muscles 
which  have  their  origin  in  this  region,  and  extends 
along  the  iliac  margin  of  the  sacrum,  so  as  to  arise  also 
from  the  posterior  third  of  the  spine  of  the  ilium.^ 
Besides  these  origins,  the  latissimus  dorsi  has  four  fleshy 
heads  from  the  sides  of  the  four  inferior  false  ribs, 
which  are  interlocked  with  the  inferior  heads  of  the 
obliquus  externus  abdominis. 

From  this  extended  origin  the  fibres  converge,  so 
as  to  form  the  posterior  fold  of  the  axilla,  and  to  termi- 
nate in  a flat,  thick  tendon,  of  two  inches  in  breadth, 
which  is  inserted  into  the  posterior  ridge  of  the  groove 
of  the  os  humeri.  The  upper  part  of  this  muscle 
passes  over  the  inferior  angle  of  the  scapula,  and  de- 
rives a fasciculus  of  fibres  from  it. 

* This  origin  frequently  is  tendinous  at  the  back  part  of  the 
ilium,  and  fleshy  in  front.  * 


342 


OF  THE  TRUNK. 


It  draws  the  os  humeri  downwards  and  backwards. 

Detacii  now  the.  trapezius  from  its  origin  and  turn 
it  over  the  shoulder.  Begin  also  to  detach  the  latissi- 
mus  dorsi  from  its  origin  above,  turning  downwards  the 
upper  edge  of  the  muscle  as  the  separation  goes  on.  By- 
doing  so,  in  a little  time  is  brought  into  view  the  upper 
edge  of  the 

Serratus  Inferior  Posticus.  The  origin  of  this 
muscle  is  inseparably  united  to  that  of  the  latissimus 
dorsi,  therefore  to  view  it  properly,  let  the  fleshy  part 
of  the  latissimus  be  detached  from  the  fascia  lumborum. 
We  shall  then  see  that  the  serratus  arises  by  a tendi- 
nous membrane  from  the  two  inferior  spines  of  the 
back,  and  the  three  superior  of  the  loins. 

It  is  inserted  by  fleshy  digitations  into  the  under 
edge  of  the  four  inferior  ribs. 

It  draws  the  ribs  downwards,  and  is  an  antagonist  to 
the  diaphragm  in  some  respects,  but  more  particularly 
to  the  serratus  superior  posticus. 

The  removal  of  the  trapezius  above,  brings  into  view 
several  muscles,  the  most  superficial  of  which  are  the 
rhomboid,  there  being  two  together  looking  very  much 
like  one. 

The  Rhomboideus  Minor  is  above.  It  is  a nar- 
row muscle  which  ai’ises  by  a thin  tendon  from  the 
three  inferior  spines  of  the  neck,  and  passing  obliquely 


MUSCLES  OF  THE  BACK- 


343 


downwards,  is  inserted  into  the  base  of  the  scapula  op- 
posite the  origin  of  its  spine. 

The  Rhomboideus  Major  arises  also  by  a thin  ten- 
don from  the  last  spine  of  the  neck,  and  from  the  four 
superior  of  the  back,  and  is  inserted  into  all  the  base 
of  the  scapula  below  its  spine. 

These  muscles  draw  the  scapula  upwards  and  back- 
wards. Detach  them  from  their  origins,  which  shows 
next. 

The  Serratus  Superior  Posticus,  arising  by  a 
thin  tendon  from  the  three  inferior  spines  of  the  neck 
and  the  two  superior  of  the  back,  and  inserted  into  the 
second,  third,  fourth  and  fifth  ribs  by  tendinous  and 
fleshy  slips,  a little  beyond  their  angles. 

This  muscle  draws  the  ribs  upwards.  A good  view 
of  the  serratus  major  anticus  where  it  is  inserted  into 
the  base  of  the  scapula,  and  of  its  situation  between 
the  thorax  and  scapula,  is  obtained  at  this  stage  of  the 
dissection.  The  muscle  itself,  in  consequence  of  aris- 
ing on  the  anterior  lateral  parts  of  the  thorax,  has  been 
considered  in  the  remarks  preliminary  to  the  study  of 
that  cavity. 

The  Levator  Scapula  is  placed  between  the  pos- 
terior edge  of  the  sterno-cleido-mastoideus  and  the  an- 
terior of  the  trapezius:  its  lower  end  is  just  above  the 


344 


OF  THE  TRUNK. 


J 

Rhomboideus  Minor..  It  arises  by  rounded  tendons 
from  the  three  or  five  superior  transverse  processes  of 
the  neck,  between  the  scaleni  muscles  and  the  splenius 
colli. 

It  is  inserted  fleshy  into  that  part  of  the  base  of  the 
scapula  above  the  origin  of  its  spine.  As  its  name  ex- 
presses, it  draws  the  scapula  upwards.  A good  view 
of  this  muscle  may  be  obtained  in  the  front  dissection 
of  the  neck. 

The  Splenius  muscle  comes  next;  its  inferior  ex- 
tremity is  under  the  serratus  superior,  but  the  prin- 
cipal part  of  it  is  covered  by  the  trapezius.  It  arises 
from  the  spinous  processes  of  the  five  inferior  cervical, 
and  of  the  four  superior  dorsal  vertebrae. 

It  is  inserted  into  the  back  of  the  mastoid  process 
and  a small  part  of  the  adjacent  portion  of  the  os  oc- 
cipitis,  and  also  into  the  transverse  processes  of  the  two 
superior  cervical  vertebrae.  It  is  customary  to  consider 
the  part  which  goes  to  the  head  as  Splenius  Capitis, 
and  the  part  below  as  Splenius  Colli;  the  latter,  in  that 
case,  is  said  to  arise  from  the  third  and  fourth  dorsal 
vertebrae.  It  draws  the  head  and  neck  backwards. 

Between  the  spinous  processes  of  the  vertebrae  and 
the  angles  of  the  ribs,  on  either  side,  there  is  a deep  fossa 
filled  up  by  muscles,  some  of  them  large  and  powerful; 
the  most  striking  are  the  Sacro  Lumbalis  and  the  Lon- 
gissimus  Dorsi. 


MUSCLE'S  OF  THE  BACK. 


345 


The  Sacro  Lumbalis  and  Longissimus  Dorsi 
have  a common  origin  from  the  back  of  the  pelvis  and 
of  the  lumbar  vertebrae,  and  extend  to  the  top  of  the 
thorax.  They  arise,  tendinous  externally,  and  fleshy 
internally,  from  the  posterior  surface  of  the  sacrum  by 
its  external  margin  and  spinous  processes ; they  arise 
also,  tendinous,  from  the  spinous  processes,  and  fleshy, 
from  the  ends  of  the  transverse  processes  of  all  the 
vertebrae  of  the  loins  and  from  the  posterior  part  of  the 
spine  of  the  ilium.  From  the  under  surface  of  this 
common  belly,  two  tendinous  and  fleshy  heads  are  in- 
serted into  the  inferior  edge  of  the  transvei*se  process 
of  each  lumbar  vertebra,  the  smaller  near  its  root  and 
the  larger  near  its  extremity.  On  a level  with  the 
lowest  rib,  and,  indeed,  somewhat  below  it,  a fissure 
occurs  in  the  muscle  which  divides  it  into  the  two 
parts. 

The  Longissimus  Dorsi  is  nearest  the  spine ; it  is  in- 
serted, by  small  double  tendons  proceeding  from  its 
internal  surface,  into  the  ends  of  the  transverse  pro- 
cesses of  all  the  vertebrae  of  the  back  except  the  first. 
It  also,  from  its  outer  edge,  sends  long  slender  tendons, 
by  which  it  is  inserted  into  the  under  edges  of  all  the 
I’ibs  near  their  angles,  except  the  two  inferior. 

The  Sacro  Lumbalis  is  inserted  from  its  outer  edge 
into  all  the  ribs  at  their  angles,  by  long  and  thin  ten- 
dons, which  are  longer,  the  higher  they  are  inserted. 

By  turning  over  this  muscle  from  the  other,  towards 
the  ribs,  one  may  see  coming  from  the  eight  lower 


X X 


346. 


OF  THE  TRUNK. 


ribs,  as  many  slips,  which  run  into  the  under  surface  of 
the  sacro  lumbalis;  they  are  the  Musculi  Accessorii  ad 
Sacro  Lumbalem. 

These  two  muscles  keep  the  spine  erect,  and  draw 
down  the  ribs. 

Between  the  ends  of  the  spinous  processes  and  the 
edge  of  the  longissimus  dorsi,  is  a muscle  almost 
entirely  tendinous,  and  scarcely  to  be  distinguished 
from  the  latter,  both  in  consequence  of  its  close  con- 
nexion with  it  and  of  its  insignificant  size.  At  its 
lower  part,  it  is  absolutely  a portion  of  the  Longissimus, 
and  can  be  separated  from  it  only  by  an  unnatural 
division.  It  is  a mere  string  lying  along  the  sides  of 
the  spinous  processes,  and  is  called  from  its  origin  and 
insertion,  the  Spinalis  Dorsi. 

The  Spinalis  Dorsi  arises  tendinous  from  the 'spi- 
nous processes  of  the  two  superior  lumbar,  and  of  the 
three  inferior  dorsal  vertebrae,  and  is  inserted  tendi- 
nous into  the  spinous  processes  of  the  nine  superior 
dorsal  vertebrae,  except  the  first. 

It  tends  to  keep  the  spine  erect.  Tui'n  now  the 
splenius  from  its  insertions,  which  exhibits  several 
muscles  under  it. 

The  Cervicalis  Descendens  is  a small  muscle 
placed  at  the  upper  portion  of  the  thorax,  between  the 
insertions  of  the  sacro  lumbalis,  and  of  the  longissimus 

/ 


MUSCLES  OF  THE  BACK.  347 

doi-si  into  the  upper  ribs;  it  looks,  at  first,  very  much 
like  a continuation  or  appendix  of  the  first,  running  to 
the  cervical  vertebrae. 

This  muscle  arises  from  the  upper  edges  of  the 
four  superior  ribs  by  long  tendons;  it  forms  a small 
belly,  which  is  inserted  into  the  transverse  processes 
of  the  fourth,  fifth,  and  sixth  vertebrae  of  the  neck, 
between  the  levator  scapulae  and  splenius  colli,  by  three 
distinct  tendons. 

It  draws  the  neck  backwards. 

The  Traxsversalis  Cervicis  is  on  the  inner  side 
of  the  last  and  in  contact  with  it,  being  about  the  same 
size,  and  having  very  much  the  same  course  and  ap- 
pearance. It  is  considered  as  an  appendage  to  the 
longissimus  dorsi. 

It  arises  from  the  transverse  processes  of  the  five 
superior  dorsal  vertebrae  by  distinct  tendons,  and  forms 
a narrow  fleshy  belly,  which  is  Inserted  by  distinct 
tendons  also,  into  the  transverse  processes  of  the  five 
middle  cervical  vertebrae.  It  draws  the  head  back- 
wards. 

The  Trachelo  Mastoideus  is  at  the  imier  side  of 
the  last  muscle,  in  contact  with  it. 

It  arises,  by  distinct  tendinous  heads,  from  the  trans- 
verse processes  of  the  three  superior  vertebrae  of  the 
back,  and  of  the  five  inferior  of  the  neck,  and  is  insert- 


348 


OF  THE  TRUNK. 


ed,  by  a thin  tendon,  into  the  posterior  edge  of  the 
mastoid  process. 

The  dorsal  origins  are  frequently  deficient  or  irre- 
gular. It  draws  the  head  baekwards. 

The  CoMPLEXus,  a fine  large  muscle,  is  situated  at 
the  inner  face  of  the  trachelo  mastoideus,  and  is  readily 
recognized  by  showing  itself  between  the  bellies  of  the 
two  splenii  capitis,  just  below  the  occiput.  A quantity 
of  tendinous  matter  exists  in  its  middle,  which  gives  it 
the  complicated  appearance  from  whence  its  name  is 
derived. 

It  arises,  by  tendinous  heads,  from  the  seven  supe- 
rior dorsal,  and  the  four  inferior  cervical  vertebrae  by 
their  transverse  processes;  aiso  by  a fleshy  slip  from 
the  spinous  process  of  the  first  dorsal.  It  is  inserted 
into  the  inferior  part  of  the  os  occipitis  by  the  surface 
between  the  upper  and  lower  transverse  ridges,  and 
on  the  outside  of  the  vertical  ridge  which  exists  in  the 
middle  of  the  bone. 

It  draws  the  head  backwards. 

The  Semispinalis  Colli  is  a muscle  which  passes 
obliquely  from  transverse  to  spinous  processes,  and  is 
situated  between  the  complexus  and  the  multifidus 
spinae;  the  course  of  its  fibres  renders  it  difficult  to  be 
distinguished  from  the  latter. 

It  arises  from  the  transverse  processes  of  the  six 
upper  vertebrae  of  the  back,  by  tendons  which  are  in- 


MUSCLES  OF  THE  BACK. 


349 


volved  with  those  of  the  adjacent  muscles,  and  passes 
up  to  the  neck,  to  be  inserted  into  the  sides  of  the  spi- 
nous processes  of  the  five  middle  cervical  vertebrae. 

It  extends  the  neck  obliquely  backwards. 

The  Semispinalis  Dorsi  is  lower  down  on  the 
spine,  and  with  difficulty  distinguished  from  the  mul- 
tifidus,  like  the  other,  passing  from  transverse  to  spi- 
nous processes.  It  lies  under  the  longissimus  dorsi, 
between  it  and  the  multifidus. 

This  muscle  arises  by  tendons  connected  with  those 
of  the  other  muscles,  from  the  transverse  processes  of 
the  seventh,  eighth,  ninth,  and  tenth  dorsal  vertebrae, 
and  passes  upwards  obliquely,  to  be  inserted,  tendi- 
nous, into  the  sides  of  the  spinous  processes  of  the  two 
lower  cervical,  and  five  upper  dorsal  vertebrae. 

It  draws  the  spine  obliquely  backwards. 

The  MULTIFIDUS  Spin.®  lies  under  the  muscles  as  yet 
mentioned,  close  to  the  bones  of  the  spine;  in  order  to 
see  it  well,  they,  therefore,  should  all  be  cut  away. 

It  has  its  commencement,  tendinous  and  fleshy,  on 
the  back  of  the  sacrum,  being  connected  to  its  spinous 
processes  and  posterior  surface,  also  to  the  back  part 
of  the  spine  of  the  ilium.  It  there  forms  a belly  of 
sufficient  magnitude  to  fill  up  much  of  the  cavity  be- 
tween the  spines  of  the  sacrum  and  the  posterior  part 
of  the  ilium.  It  arises  also  from  the  roots  of  the  ob- 
lique and  transverse  processes  of  all  the  vertebrse  of  the 


350 


OF  THE  TRUNK. 


loins,  of  the  back,  and  of  the  four  inferior  of  the  neck. 

The  multifidus  is  inserted,  tendinous  and  fleshy,  into 
the  roots  and  sides  of  the  spinous  processes  of  all  the 
vertebrae  of  the  loins,  of  the  back,  and  of  the  five  in- 
ferior of  the  neck. 

This  muscle  consists  of  a great  number  of  small 
bellies,  which  are  parallel^o  each  other,  arising  from  a 
transverse  process,  and  going  to  the  spinous  process 
either  of  the  first  or  second  vertebra  above  it. 

It  twists  the  spine  backwards  and  keeps  it  erect. 

Between  the  head,  and  the  first  and  second  verte- 
brae, and  between  the  two  latter,  there  are,  on  eacli 
side,  four  small  muscles,  intended  for  the  motion  of 
these  parts  upon  each  other.  They  are  brought  into 
view  by  the  removal  of  the  complexus. 

The  Rectus  Capitis  Posticus  Ma.ior  arises  ten- 
dinous and  fleshy,  from  the  extremity  of  the  spinous 
process  of  the  dentata,  and  is  inserted  into  the  inferior 
transverse  ridge  of  the  os  occipitis,  and  part  of  the  sur- 
face below  it. 

Its  shape  is  pyramidal,  the  apex  being  below.  It 
turns  the  head,  and  also  draws  it  backwards. 

The  Rectus  Capitis  Posticus  Mixor  is  at  the 
internal  edge  of  the  first.  It  arises  tendinous  from  the 
tubercle  on  the  back  part  of  the  first  vertebra,  and  is 
inserted  into  the  internal  end  of  the  inferior  ti’ansversf 


MUSCLES  OF  THE  BACK. 


351 


ridge  of  the  os  occipitis,  and  into  part  of  the  surface 
between  it  and  the  foramen  magnum. 

It  is  also  pyramidal^  with  the  apex  downwards.  It 
draws  the  head  backwards. 

The  Obliquus  Capitis  Superior  arises  from  the 
transverse  process  of  the  first  cervical  vertebra,  and 
is  inserted  into  the  inferior  transverse  ridge  of  the  os 
occipitis,  behind  the  posterior  part.of  the  mastoid  pro- 
cess, and  beneath  the  complexus  muscle. 

It  draws  the  head  backwards. 

The  Obliquus  Capitis  Inferior  arises  from  the 
side  of  the  spinous  process  of  the  dentata,  and  is  in- 
serted into  the  back  part  of  the  transverse  process  of 
the  first  vertebra  of  the  neck. 

It  rotates  the  first  vertebra  on  the  second. 

The  Interspinales  are  small  short  muscles,  placed 
between  the  spinous  processes  of  contiguous  vertebrae. 
In  the  neck  they  are  double,  in  consequence  of  its 
spinous  processes  being  bifurcated;  in  the  back  they  are 
almost  entirely  tendinous ; in  the  loins  they  are  single 
and  well  marked. 

They  draw  the  spinous  processes  together,  and  keep 
the  spine  erect. 

The  Intertransversarii  are  also  short  muscles 
placed  in  a similar  manner,  between  the  transverse  pro- 


352 


OF  THE  TRUNK. 


cesses  of  the  vertebrae.  In  the  neck  they  are  double,  in 
the  back  they  are  small,  tendinous,  and  not  well  express- 
ed, and  in  the  loins  they  are  single  and  well  seen. 

They  draw  the  transverse  processes  together,  and 
will,  of  course,  bend  the  spine  to  one  side. 

The  Levatores  Costarum  are  small  muscles  con- 
cealed by  the  sacro  lumbalis  and  longissimus  dorsi, 
and  pass  from  the  transverse  processes  of  the  last 
cervical  and  the  eleven  superior  doi'sal  vertebrae,  to  the 
upper  edges  of  all  the  ribs.  They  are  twelve  on  either 
side  of  the  spine,  are  tendinous  in  their  origins  and  in- 
sertions, with  intermediate  muscular  bellies. 

The  upper  ones  are  small  and  thin,  and  they  increase 
in  magnitude  as  they  descend.  From  the  inferior  edge 
of  nearly  all  these  muscles  a fleshy  slip  is  detached, 
which  passes  over  the  rib  next  below  its  origin,  to  the 
second  rib  below,  and  occasionally  to  the  third.  These 
slips  are  called  Levatores  Costarum  Longiores.  The 
others  which  descend  from  the  transverse  process  to 
the  rib  next  below,  are  called  Levatores  Costarum 
Breviores. 

These  muscles  are  parallel  in  their  obliquity,  with 
the  external  intercostals,  and  are  not  very  obviously 
separated  from  them.  They  perform  the  same  ser- 
vice,  that  of  elevating  the  ribs. 


PART  III. 


O F T-H  E EXTREMITIES. 


CHAPTER  I. 

Of  the  Upper  Extremities. 


Section  I. 

Of  the  Fascia. 

* The  Upper  Extremity,  consisting  of  shoulder,  arm, 
fore-arm,  and  hand,  has  not  so  regular,  or  so  strong 
an  investment  of  fascia  as  the  thigh.  In  the  shoulder, 
excepting  its  back  part,  and  in  the  arm,  this  envelope 
has  but  few  ligamentous  fibres  in  it,  and  is  principally 
condensed  cellular  membrane,  which  ought  to  be  re- 
moved with  the  skin;  but  in  the  fore-arm  its  character 
is  better  developed,  and  is  there  decidedly  aponeurotic. 
The  aponeurosis  of  the  fore-arm  forms  a complete 

y y 


354 


OF  THE  UPPER  EXTREMITIES. 


sheath  for  its  muscles.  It  is  connected  with  the  bony 
prominences  at  the  elbow  joint,  more  particularly  the 
external  and  internal  condyle,  with  the  ulnar  side  of  the 
tendon  of  the  biceps  muscle,  and  the  olecranon  process 
of  the  ulna;  and  passes  down  to  the  carpus,  where  it 
terminates  both  anteriorly  and  posteriorly  in  the  an- 
nular ligament  of  the  wrist.  It  is  attached  to  the 
ulna  along  its  internal  margin,  from  the  elbow  joint  to 
the  wrist,  and  several  muscles  arise  from  its  interior 
surface. 

It  is  unnecessary  to  undertake,  from  the  first,  a 
regular  dissection  of  this  fascia,  inasmuch  as  it  will  be 
gradually  exposed  in  proceeding  with  the  muscles. 
This  extremity  is  most  conveniently  studied  by  detach- 
ing it  from  the  trunk,  taking  care  to  have  the  clavicle 
with  it. 


Section  II. 

Of  the  Muscles  of  the  Upper  Extre?nities. 

The  Muscles  situated  on  the  shoulder  are  six  in 
number;  they  extend,  for  the  most  part,  from  the 
scapula  to  the  head  and  neck  of  tlie  os  humeri. 


MUSCLES. 


355 


1.  The  Deltoides  arises  from  the  inferior  edge  of 
the  whole  spine  of  the  scapula,  from  the  outer  margin 
of  the  acromion  process,  and  from  the  exterior  third 
of  the  clavicle.  Its  origin,  for  the  most  part,  is  tendi- 
nous and  fleshy  mixed;  but  at  its  posterior  part,  it  is 
entirely  tendinous. 

It  is  inserted  by  a tendinous  point,  into  the  triangu- 
lar rough  surface,  on  the  outer  side  of  the  os  humeri, 
near  its  middle.  It  raises  the  os  humeri  to  a horizon- 
tal line  with  the  acromion. 

The  deltoid  is  situated  just  beneath  the  skin,  and 
forms  the  cushion,  which  protects  and  gives  rotundity 
to  the  shoulder  joint.  Its  general  configuration  is  tri- 
angular, and,  when  spread  out,  its  upper  margin  is 
much  more  extensive  than  one  would  suppose,  from  be- 
ing opposed  to  the  insertion  of  the  trapezius.  Its  fibres 
do  not  converge  regularly  to  its  insertion  like  the 
radii  of  a circle,  but  the  whole  muscle  is  divided  into 
several  parts;  the  interposition  of  intermuscular  ten- 
dons into  which,  affecting  the  course  of  the  fibres, 
makes  several  portions  of  the  deltoid  look  penniform, 
and  others  like  smaller  deltoids  introduced  into  the 
larger. 

The  deltoid  covers  the  insertion  of  the  peetoralis 
major,  latissimus  dorsi,  and  teres  major,  besides  that 
of  the  other  muscles  of  the  shoulder.  It  also  conceals 
the  origin  of  the  biceps  flexor  cubiti  and  of  the  coraco 
brachialis.  Its  insertion  is  between  the  triceps  exten- 


356 


OF  THE  UPPER  EXTREMITIES. 


sor  and  the  biceps  flexor,  and  above  the  origin  of  the 
brachialis  internus. 

The  deltoid  should  be  detached  from  its  origin  and 
thrown  down,  which  gives  a good  view  of  the  other 
muscles. 

2.  The  Supra  Spinatus  arises  fleshy  from  the 
whole  fossa  supra  spinata  which  it  fills  up,  and  from 
its  margins.  Forwards  it  terminates  in  a thick  robust 
tendon,  closely  connected  with  the  capsular  ligament 
of  the  joint,  which  passes  under  the  jugum  formed  by 
the  articulation  of  the  acromion  with  the  clavicle. 

It  is  inserted  tendinous  into  the  inner  face  of  the 
great  tubercle  of  the  os  humeri,  and  will  assist  in 
raising  it. 

3.  The  Infra  Spinatus  arises  fleshy  from  all  that 
portion  of  the  dorsum  scapulas  below  its  spine,  from 
the  spine  as  far  as  the  cervix,  and  from  the  several 
margins  of  the  fossa  infraspinata.  Its  fibres  pass  ob- 
liquely to  a middle  tendon,  which  adheres  closely  to 
the  capsular  ligament,  and  goes  under  the  projection  of 
the  acromion. 

This  tendon  is  inserted  into  the  middle  face  of  the 
greater  tubercle  of  the  os  humeri. 

The  infra  spinatus  rolls  the  os  humeri  outwards  and 
backwards. 


4.  The  Teres  Minor  is  situated  at  the  inferior 


MUSCLES. 


357 


margin  of  the  infraspinatus,  in  the  fossa  of  the  inferior 
costa  scapulae,  and  looks  very  much  like  a part  of  the 
infra  spinatus,  to  which  it  occasionally  adheres  so  close- 
ly, as  to  be  separated  with  difl5,culty.  It  arises  fleshy 
from  the  whole  of  the  fossa,  from  the  margins  of  the  in- 
ferior costa,  and  from  the  cervix  of  the  bone,  to  within 
an  inch  or  so  of  its  angle. 

It  is  inserted,  tendinous  and  fleshy,  into  the  outer 
face  of  the  great  tuberosity  of  the  os  humeri,  just  be- 
low the  infra  spinatus. 

It  draws  the  humerus  downwards  and  backwards, 
and  rotates  it  outwards. 

5.  The  Teres  Major  is  situated  at  the  inferior 
edge  of  the  teres  minor.  It  arises  fleshy  from  the  pos- 
terior surface  of  the  angle  of  the  scapula,  and  from  a 
small  part  of  its  inferior  costa;  the  interstice  between 
it  and  the  teres  minor  is  considerable. 

It  is  inserted,  by  a broad  tendon,  into  the  internal 
ridge  of  the  groove  of  the  os  humeri,  along  with  the 
tendon  of  the  latissimus  dorsi.  Their  tendons,  at  first, 
are  closely  united,  but  afterwards  there  is  an  interme- 
diate cavity  lubricated  with  synovia.  The  tendon 
of  the  latissimus  dorsi  is  anterior,  and  the  lower  edge 
of  the  teres  extends  further  down  the  arm  than  that 
of  the  other. 

It  rolls  the  humerus  inwards,  and  draws  it  down- 
wards and  backwards. 


358 


OF  THE  UPPER  EXTREMITIES. 


6.  The  SuBSCAPULARis  occupies  all  the  thoracic 
surface  of  the  scapula,  being  between  it  and  the  ser- 
ratus  major  anticus.  It  arises  fleshy  from  the  whole 
base,  superior  and  inferior  costa,  and  venter  of  the 
scapula;  it  is  divided  into  several  columns  which  look 
somewhat  like  distinct  muscles,  but  which  all  termi- 
nate, in  a thick,  robust  tendon  that  adheres  to  the  in- 
ferior surface  of  the  capsular  ligament. 

This  tendon  is  inserted  into  the  lesser  tubercle  of 
the  os  humeri.  The  subscapularis  rolls  the  bone  in- 
wards and  draws  it  downwards. 

The  Muscles  of  the  arm  are  five  in  number,  three 
anterior,  and  two  posterior. 

1.  The  Biceps  Flexor  Cubiti  is  situated  imme- 
diately beneath  the  integuments,  and  forms  the  swell 
so  obvious  in  the  middle  front  part  of  most  arms.  It 
arises  by  two  heads;  the  first  called  the  long,  is  a round 
tendon,  which  comes  from  the  superior  exti’emity  of 
the  glenoid  cavity  of  the  scapula,  passes  through  the 
shoulder  joint,  and  through  the  groove  of  the  os  hu- 
meri. The  second  head  arises,  tendinous,  from  the 
extremity  of  the  coracoid  process  of  the  scapula,  in 
company  with  the  coraco-brachialis  muscle.  The 
fleshy  bellies  in  which  these  tendons  terminate,  unite 
with  each  other,  a few  inches  below  the  shoulder  joint, 
to  form  a common  muscle.  At  first,  they  are  only  con- 


MUSCLES. 


359 


iiected  by  loose  cellular  substance,  but  about  half  way 
down  the  arm  they  are  inseparably  united. 

The  biceps  terminates  below  in  a flattened  oval  ten- 
don, and  passes  in  front  of  the  elbow  joint  to  be  insert- 
ed into  the  posterior  rough  part  of  the  tubercle  of  the 
radius.  A bursa  mucosa  is  placed  between  the  tendon 
and  the  front  of  the  tubercle,  the  surface  of  the  latter 
being  covered  with  cartilage.  From  the  ulnar  side  of 
this  tendon  proceeds  a fascia  running  into  that  of  the 
fore- arm. 

The  relative  position  of  the  biceps  is  as  follows:  Its 
long  head  is  first  within  the  cavity  of  the  capsular 
ligament,  and  then  between  the  tendons  of  the  latissi- 
mus  dorsi  and  pectoralis  major,  where  it  is  bound 
down  by  strong  ligamentous  fibres.  The  tendon  below 
is  superficial,  and  may  be  easily  felt  by  flexing  the 
extremity;  but  its  insertion  dips  down  between  the 
pronator  teres  and  supinator  radii  longus. 

This  muscle  flexes  the  fore-arm. 

2.  The  CoRACo  Brachialis  is  situated  at  the  up- 
per internal  side  of  the  arm,  at  the  inner  edge  of  the 
short  head  of  the  biceps  muscle,  with  which  it  is  con- 
nected for  three  or  four  inches.  It  arises  tendinous 
and  fleshy,  from  the  middle  face  of  the  point  of  the 
coracoid  process  of  the  scapula,  in  common  with  the 
short  head  of  the  biceps  muscle. 

It  is  inserted,  tendinous  and  fleshy,  into  the  inter- 
nal side  of  the  middle  of  the  os  humeri,  by  a rough 


360 


OF  THE  UPPER  EXTREMITIES. 


ridge,  just  below  the  tendons  of  the  latissimus  del’s! 
and  teres  major,  and  in  front  of  the  brachialis  exter- 
niis.  From  the  lower  end  of  this  muscle  proceeds  an 
intermuscular  ligament  to  the  internal  condyle  of  the 
humerus,  which  separates  the  brachialis  interims  from 
the  third  head  o^the  triceps. 

Tliis  muscle  draws  the  arm  upwards  and  forwards. 

3.  The  Brachialis  Internus  is  situated  immedi- 
ately beneath  the  biceps,  and  is  concealed  by  it,  ex- 
cepting the  outer  edge.  It  has  a bifurcated  fleshy  ori- 
gin, from  the  middle  front  face  of  the  os  humeri,  on 
each  side  of  the  insertion  of  the  deltoid,  and  its  origin 
is  continued  fleshy  from  this  point  downwards,  from 
the  whole  front  of  the  bone  to  within  a very  small  dis- 
tance of  its  articular  surface. 

It  is  inserted,  by  a strong  short  tendon,  into  tin 
rough  surface  at  the  root  of  the  coronoid  process  of  the 
ulna. 

The  brachialis  flexes  the  fore-arm,  and,  by  passing 
in  front  of  the  elbow  joint,  strengthens  the  latter  very 
much.  Its  lower  part  lies  under  the  tendon  of  the 
biceps,  and  between  the  pronator  teres  and  the  supi- 
nator longus. 

4.  The  Triceps  Extensor  Gubiti  forms  the 
whole  of  the  fleshy  mass  on  the  back  of  the  arm:  it 
therefore  occupies  the  space  between  the  integuments 
and  the  bone.  It  arises  by  three  heads.  The  first. 


MUSCLES. 


361 


called  Longus,  comes,  by  a flattened  tendon,  from  a 
rough  ridge  on  the  inferior  edge  of  the  cervix  scapulae. 
The  second,  called  the  Brevis,  arises,  by  a sharp,  ten- 
dinous, and  fleshy  beginning,  from  a slight  ridge  on 
the  outer  back  part  of  the  os  humeri  just  below  its 
head.  The  third  head,  called  Brachialis  Externus, 
arises,  by  an  acute  fleshy  beginning,  from  the  inner 
side  of  the  os  humeri,  near  the  insertion  of  the  teres 
major.  This  muscle,  both  at  its  external  and  internal 
edge,  is  separated  from  the  muscles  in  front  of  the  arm, 
by  a ligamentous  septum,  which  arises  near  the  middle 
of  the  os  humeri,  and  runs  to  its  condyles.  The  whole 
back  of  the  os  humeri,  as  well  as  the  posterior  surface 
of  these  intermuscular  septa,  are  occupied  by  the  origin 
of  the  triceps.  The  muscular  fibres  run  in  various 
directions  according  to  their  respective  heads  and 
places  of  origin. 

At  the  inferior  end  of  the  muscle  is  found  a broad 
tendon  which  covers  its  posterior  face.  This  tendon 
is  inserted  into  the  base  or  back  part  of  the  olecranon, 
and  into  the  ridge  leading  down  the  ulna  on  its  radial 
side. 

The  triceps  extends  the  fore- arm.  Its  bellies  unite 
above  the  middle  of  the  os  humeri,  but  the  interstices 
between  them  may  be  observed  much  lower  down. 

Connected  with  the  last  is  a muscle  which  should  be 
dissected  at  the  same  time,  as  it  has  corresponding 


z z 


362 


OF  THE  UPPER  EXTREMITIES. 


functions,  and  looks  very  much  like  an  appendage  of 
the  triceps;  it  is  the 

5.  Anconeus.  This  is  a small  triangular  muscle 
just  beneath  the  skin,  at  the  outer  posterior  part  of  the 
elbow  joint.  It  arises  tendinous  from  the  posterior 
lower  part  of  the  external  condyle  of  the  os  humeri, 
adheres  to  the  capsular  ligament  of  the  joint,  and  is 
partly  covered  by  the  tendon  of  the  triceps. 

It  is  inserted,  fleshy  and  thin,  into  the  ridge  on  the 
outer  part  of  the  head  of  the  ulna  leading  from  the 
oleeranon,  and  fills  up  the  triangular  depression  found 
there. 

It  extends  the  fore-arm. 


Section  III. 

Of  the  Muscles  in  front  of  the  Ferre- Arm. 

The  most  of  these  muscles  arise  from  the  inner  con- 
dyle of  the  os  humeri,  and  from  the  ridge  leading  to 
it,  and  are,  either  directly  or  indirectly,  flexors  of  the 
fore-arm  upon  the  arm.  This  fact  should  be  impress- 
ed on  the  mind  of  the  student,  as  it  simplifies  much 
the  act  of  committing  them  to  memory.  The  syste- 
matic treatises  of  anatomy  describe  the  origin  of  each 


MUSCLES. 


363 


muscle  as  if  it  were  totally  distinct  from  the  rest;  the 
student  will  soon  correct  the  error  arising  from  this^ 
and  learn  that  the  heads  of  all  these  muscles  are  con- 
nected to  contiguous  heads,  by  adhesion  and  by  inter- 
muscular ligaments,  and  that  there  would  be  almost  as 
much  propriety  in  describing  them  as  having  a common 
origin,  as  there  is  in  considering  them  so  insulated. 

There  are  eight  muscles  situated  on  the  front  of  the 
fore-arm,  some  of  which  are  superficial  and  others 
deep-seated. 

1.  The  Pronatoe  Radii  Teres  is  just  beneath  the 
fascia  of  the  fore-arm,  and  forms  the  radial  side  of  the 
muscles  of  the  internal  condyle.  It  arises  fleshy  from 
the  anterior  face  of  the  internal  condyle  of  the  hume- 
rus, and  tendinous  from  the  eoronoid  process  of  the  ulna. 
It  passes  veiy  obliquely  across  the  fore-arm  at  the  in- 
ternal edge  of  the  brachialis  internus  muscle,  and  is 

Inserted,  tendinous  and  fleshy,  into  the  external 
back  part  of  the  radius  just  below  the  insertion  of  the 
supinator  radii  brevis,  occupying  thereby  about  two 
inches  of  the  middle  of  the  bone. 

It  rolls  the  hand  inwards. 

2.  The  Flexor  Manus  vel  Carpi  Radialis  is 
placed  at  the  ulnar  side  of  the  last  muscle,  and  is  also 
superficial.  It  arises,  by  a narrow  tendon,  from  the 
lower  front  part  of  the  internal  condyle  of  the  hume- 


364 


OF  THE  UPPER  EXTREMITIES. 


rus;  fleshy  from  the  intermuscular  ligaments,  fascia, 
and  from  the  upper  part  of  the  ulna.  It  forms  a 
thick,  fleshy  belly,  terminating  below  in  a tendon, 
which  passes  under  the  anterior  annular  ligament  of  the 
wrist,  and  runs  through  a groove  in  the  os  trapezium. 

It  is  inserted,  tendinous,  into  the  base  of  the  meta- 
carpal bone  of  the  fore-finger,  in  front. 

It  bends  the  hand. 

3.  The  Palmaris  Loxgus  is  at  the  ulnar  side  of 
the  flexor  carpi  radialis,  and  is  superficial.  Sometimes 
it  does  not  exist.  It  is  a small  short  muscle  terminating 
in  a long  slender  tendon,  and  arises  by  a small  tendon 
from  the  internal  condyle,  and  fleshy  from  the  inter- 
muscular ligaments  on  each  of  its  sides'. 

It  is  inserted,  tendinous,  into  the  humeral  margin 
of  the  ligamentum  annulare  anterius  near  the  root  of 
the  thumb,  and  a division  of  its  tendon  passes  on  to  the 
aponeurosis  palmaris. 

It  bends  the  hand,  and  makes  tense  the  palmar  apo- 
neurosis. 

4.  The  Flexor  Manus  vel  Carpi  Ulnaris  occu- 
pies, among  the  superficial  muscles,  the  ulnar  side  of 
the  fore-arm.  It  arises,  tendinous,  from  the  internal 
condyle  of  the  humerus,  fleshy,  from  the  upper  inter- 
nal side  of  the  olecranon,  and,  by  a tendinous  expan- 
sion much  connected  with  the  fascia  of  the  fore-arm. 


MUSCLES. 


365 


from  the  ridge  at  the  internal  side  of  the  ulna  to  within 
three  or  four  inches  of  the  wrist. 

It  is  inserted  into  the  humeral  side  of  the  os  pisi- 

r 

forme  by  a round  tendon,  which  arises  high  up  at  the 
radial  margin  of  the  muscle,  and  into  which  the  mus- 
cular fibres  run.  Sometimes  the  tendon  is  continued 
over  the  os  pisiforme,  so  as  to  be  likewise  inserted  into 
the  base  of  the  metacarpal  bone  of  the  little  finger. 

It  bends  the  hand. 

r 

5.  TheFLEXOR  Digitorum  Sublimis  Perforatus 
is  concealed  very  much  by  the  muscles  just  enumera- 
ted, in  consequence  of  being  placed  between  them.  To 
get  a good  view  of  its  origin  they  all  should  be  cut 
away  from  the  os  humeri.  It  arises,,  tendinous  and 
fleshy,  from  the  internal  condyle  of  the  os  humeri; 
tendinous,  from  the  coronoid  process  of  the  ulna,  and 
fleshy,  from  the  tubercle  of  the  radius;  the  latter  part 
of  its  origin  is  extended  tendinous  obliquely,  for 
three  or  four  inches  along  that  line  of  the  radius  which 
is  at  the  lower  margin  of  the  pronator  teres.  With 
these  origins  the  muscle  spreads  over  the  front  of  the 
fore-arm  at  its  upper  part,  from  the  radial  to  the  ulnar 
margin. 

From  the  lower  end  of  the  muscle,  four  distinct  ten- 
dons pass  which  commence  much  above  the  wrist,  go 
beneath  its  anterior  ligament,  and,  having  got  to  the 
palm  of  the  hand,  diverge  to  the  several  fingers.  To 
each  finger,  a tendon  is  appropriated  which  passes  in 


J66 


OF  THE  UPPER  EXTREMITIES. 


front  of  the  metacarpal  bone  to  the  phalanges;  and  is 
inserted,  after  having  split  into  two,  into  the  angles 
formed  by  the  junction  of  the  cylindrical  and  flat  sur- 
faces near  the  upper  part  of  the  second  phalanx. 

It  bends  the  second  phalanges  on  the  first ; its  action 
may  also  be  continued  so  as  to  clench  the  hand  and  to 
bend  it  on  the  arm. 

6.  The  Flexor  Digitorum  Profuxdus  Perfo- 
RANS  is  beneath  the  flexor  sublimis  and  the  flexor  ulna- 
ris.  It  arises  fleshy  from  the  oblong  concavity  of  the 
ulna  between  the  coronoid  and  the  olecranon  processes; 
fleshy  from  the  carpal  margin  of  the  base  of  the  coronoid 
process;  from  the  ulnar  portion  of  the  interosseous  liga- 
ment; and  from  the  front  of  the  upper  two-thirds  of 
the  ulna. 

The  tendons  of  this  muscle  are  different  from  those 
of  the  other;  they  commence  in  front  of  it,  like  a ten- 
dinous membrane,  which  is  gradually  divided  into  seve- 
ral fasciculi,  adhering  to  each  other  by  cellular  mem- 
brane. The  fasciculated  character  of  the  tendons  is 
still  preserved  when  they  go  under  the  anterior  carpal 
ligament,  and  until  they  begin  to  dispei’se  as  distinct 
tendons  to  the  four  fingers. 

Each  tendon,  going  in  front  of  its  metacarpal  bone 
and  of  the  corresponding  phalanges,  gets  through  the 
slit  in  the  flexor  sublimis,  and  is  inserted  into  the  front 
part  of  the  root  of  the  third  phalanx  of  the  finger. 

It  bends  the  last  joint  of  tlie  fingers,  and  by 


MUSCLES. 


367 


increased  action,  may  flex  tlie  hand  like  the  preceding 
muscle. 

7,  The  Flexor  Longus  Pollicis  lies  in  front  of 
the  radius,  but  beneath  the  flexor  sublimis.  It  arises, 
by  an  acute  fleshy  beginning,  from  the  radius  just  be- 
low its  tubercle;  also,  fleshy,  from  the  middle  two- 
thirds  of  the  front  of  the  bone,  and  from  the  radial 
portion  of  the  interosseous  ligament.  The  body  of  the 
muscle  is  joined  by  a small  fleshy  slip,  of  a tendinous 
origia  from  the  internal  condyle  of  the  humerus. 

On  the  ulnar  margin  of  this  muscle  a tendon  is  form- 
ed early,  to  which  the  fibres  pass  obliquely.  This 
tendon  goes  under  the  annular  ligament  of  the  wrist, 
through  the  fossa  formed  in  the  short  flexor  muscle 
of  the  thumb,  and  between  the  sesamoid  bones,  to 
be  inserted  into  the  base  of  the  second  phalanx  of  the 
thumb. 

It  bends  the  last  joint  of  the  thumb. 

While  performing  this  dissection  there  are  several 
minutiae  which  deserve  attention.  The  Annular  Liga- 
ment of  the  wrist  in  front,  is  a very  strong  membrane 
passing  across  the  carpus,  from  the  projection  of  the 
scaphoides  and  trapezium  on  the  radial  side  of  the 
wrist,  to  the  unciform  process  on  the  ulnar  side.  Be- 
tween it  and  the  concavity  of  the  carpus,  an  oval  fora- 
men is  formed  for  transmitting  the  tendons  of  the  seve- 
ral flexors.  These  tendons,  though  they  slide  with 


368 


OF  THE  UPPER  EXTREMITIES. 


perfect  freedom  upon  each  other,  are  connected  by  a 
dense  and  elastic  cellular  membrane,  forming  a bui’sa, 
which  has  the  power  of  keeping  them  lubricated  by  a 
synovial  secretion. 

The  Vaginal  Ligaments  of  the  Angel’s  extend  from 
the  roots  of  the  fingers  to  the  bases  of  the  third  pha- 
langes. They  are  of  a ligamento- cartilaginous  struc- 
ture, are  attached  on  either  side  to  the  anterior  edge 
of  the  phalanges,  and  are  much  thinner  as  they  pass 
over  the  fronts  of  the  finger  joints  than  elsewhere. 
They  are  inelastic,  their  internal  surface  is  extremely 
smooth,  and  kept  continually  lubricated  by  synovial 
fluid. 

Within  the  vaginal  ligaments  small  tendinous  fraena 
are  found  to  arise  from  the  first  and  second  phalanges, 
they  run  obliquely  forwards,  and  terminate  in  the  ten- 
dons of  the  two  flexor  muscles.  We  may  also  observe 
that  in  front  of  each  joint,  independently  of  the  swelling 
of  the  articular  extremities  of  the  bones,  the  capsular 
ligament  is  thickened  by  an  addition  of  cartilaginous 
matter,  by  which  a trochlea  is  formed.  This  trochlea 
facilitates  the  sliding  of  the  tendons  by  its  smoothness, 
and  the  flexions  of  the  phalanges  by  removing  the  ten- 
dons further  from  the  axis  of  motion,  after  the  same 
manner  with  the  patella. 

8.  The  Pronator  Quadratus  is  just  above  tlic 
carpal  surfaces  of  the  radius  and  ulna,  and  between 
the  other  muscles  and  the  bone.  In  the  adult  it  is 


MUSCLES. 


369 


about  two  inches  wide,  and  its  fibres  run  across  the 
fore-arm.  It  arises,  fleshy  and  tendinous,  from  the 
ridge  at  the  inner  surface  of  the  plna  near  its  lower  ex- 
tremity, and  from  the  front  of  the  bone. 

It  is  inserted  into  the  eorresponding  front  surface  of 
the  radius.  It  rotates  the  radius  inwards. 

Of  the  Muscles  on  the  Back  of  the  Fore- Arm. 

These  muscles  are  ten  in  number.  They  arise  for 
the  most  part  from  the  external  condyle  and  the  ridge 
leading  to  it,  and  are  extensors  either  of  the  fore- arm, 
or  of  the  fingers  and  hand.  Their  origins  are  less 
blended  with  each  other  than  those  of  the  flexor  mus- 
cles, nevertheless  between  several  of  them  there  are 
intermuscular  ligaments  which  connect  them  closely. 
They  are  superficial  and  deep  seated. 

1.  The  SupixATOR  Radii  Longus  is  situated  along 
the  radial  edge  of  the  fore-arm,  immediately  beneath 
the  integuments.  It  arises,  fleshy  and  tendinous,  from 
the  higher  part  of  the  ridge  leading  to  the  external 
condyle,  commencing  just  below  the  insertion  of  the 
deltoid  muscle,  and  being  here  placed  between  the 
brachialis  internus  and  the  short  head  of  the  triceps. 
It  forms  a thick,  deshy  belly,  constituting  the  external 
margin  of  the  arm  about  the  elbow  joint,  and  termi- 
nates about  the  middle  of  the  radius  in  a flat  tendon. 

It  is  inserted,  by  the  tendon,  into  a small  rough 
3 A 


370 


OF  THE  UPPER  EXTREMITIES. 


ridge  on  the  outer  side  of  the  radius,  just  above  its 
styloid  process. 

It  rolls  the  radius  outwards. 

2.  The  Extensor  Carpi  Radialis  Longior  is  si- 
tuated beneath  the  former  muscle.  It  arises,  tendinous 
and  fleshy,  from  the  space  of  the  external  ridge  of  the  os 
humeri  between  the  supinator  longus  and  the  external 
condyle.  It  forms  a short,  fleshy  belly,  which  termi- 
nates in  a flat  tendon  above  the  middle  of  the  radius. 

It  is  inserted,  by  this  tendon,  into  the  posterior  part 
of  the  root  of  the  metacarpal  bone  of  the  fore-finger 
near  the  thumb. 

It  extends  the  hand. 

3.  The  Eietensor  Carpi  Radialis  Brevior  is 
beneath  the  last,  but  projects  somewhat  beyond  it. 
It  arises,  tendinous,  from  the  posterior  and  lower  part 
of  the  external  condyle,  and  from  the  external  lateral 
ligament  of  the  elbow  joint.  It  forms  a thick,  fleshy 
belly,  placed  along  the  radius,  which  terminates  in  a 
flat  tendon  about  the  middle  of  that  bone. 

Its  tendon,  becoming  rounded,  is  inserted  into  the 
posterior  part  of  the  base  of  the  metacarpal  bone  of  the 
second  finger. 

It  extends  the  hand. 

4.  The  Extensor  Carpi  Ulnaris  is  superficial, 
and  placed  principally  parallel  with  the  ulna.  It 
arises,  tendinous,  from  the  external  condyle,  fleshy. 


MUSCLES. 


371 


from  the  intermuscular  ligament  and  inside  of  the  fas- 
cia. Crossing  very  obliquely  the  upper  part  of  the 
radius  and  the  ulna,  it  also  arises  fleshy  from  the  back 
part  of  the  latter  bone.  Its  fibres  terminate  obliquely 
ill  a tendon  which  goes  through  the  groove  of  the 
ulna. 

It  is  inserted,  by  its  tendon,  into  the  ulnar  side  of 
the  base  of  the  metacarpal  bone  of  the  little  finger. 

It  extends  the  hand. 

5.  The  Extensor  Digitorum  Communis  is  super- 
ficial, being  placed  between  the  extensor  ulnaris  and 
the  extensor  radialis  brevior.  It  arises,  tendinous, 
from  the  external  condyle,  and  fleshy,  from  the  inter- 
muscular ligament  of  the  contiguous  muscles.  As  it 
approaches  the  wrist  it  sends  off  four  tendons,  which 
pass  together  through  a common  groove  on  the  back  of 
the  radius.  On  the  back  of  the  hand  these  tendons 
diverge,  and  near  the  roots  of  the  fingers  send  cross 
slips  to  each  other. 

Each  tendon  goes  to  its  respective  finger  and  covers 
the  whole  posterior  part  of  it,  being  spread  out  into  a 
membrane,  which  adheres  to  the  phalanges  from  the 
root  of  the  first  to  the  root  of  the  last. 

The  section  of  this  muscle  appropriated  to  the  little 
finger  has  a distinct  appearance,  and  sometimes  its 
tendon  goes  through  a distinct  fossa  in  the  radius, 
from  which  causes  it  has  obtained  the  name  of  Auri- 
cularis. 


372 


OF  THE  UPPER  EXTREMITIES. 


This  muscle  extends  all  the  joints  of  the  fi.ngei's, 
being  the  antagonist  of  the  flexors. 

6.  The  Supinator  Radii  Brevis  can  only  be  well 
seen  by  detaching  the  origins  of  the  aforesaid  muscles; 
it  will  then  be  found  in  contact  with  the  radius,  making 
a close  investment  of  its  head  and  upper  third.  It 
arises,  tendinous,  from  the  external  condyle  of  the 
humerus,  tendinous  and  fleshy,  from  the  ridge  on  the 
posterior  radial  edge  of  the  ulna  which  descends  from 
its  coronoid  process. 

Its  fibres  surround,  obliquely,  the  upper  external 
part  of  the  radius,  and  are  inserted  into  its  tubercle, 
and  into  the  oblique  rough  ridge  corresponding  with 
the  upper  margin  of  the  pronator  teres.  At  the  inter- 
stice between  the  radius  and  ulna,  near  the  anterior 
edge  of  this  muscle,  a fleshy  slip  is  occasionally  seen, 
which  passes  from  the  radial  side  of  the  coronoid 
process  to  the  ulnar  edge  of  the  radius. 

This  muscle  rotates  the  radius  outwards. 

7.  The  Extensor  Ossis  Metacarpi  Pollicis 
Manus  arises,  fleshy,  from  the  posterior  part  of  the 
ulna  immediately  below  the  anconeus,  from  the  inter- 
osseous ligament,  and  from  the  back  part  of  the  radius 
just  below  the  insertion  of  the  supinator  brevis.  It 
terminates  in  a rounded  tendon,  which  passes  over  the 
tendons  of  the  radial  extensors,  and  through  a groove 
on  the  styloid  side  of  the  head  of  the  radius. 


MUSCLES. 


373 


It  is  inserted,  by  its  tendon,  into  the  base  of  the 
metacarpal  bone  of  the  thumb,  and  into  the  external 
side  of  the  trapezium. 

It  extends  the  metacarpal  bone  of  the  thumb. 

8.  The  Extensor  Minor  Pollicis  Manus  is  at 
the  ulnar  side  of  the  last  muscle.  It  arises,  tendinous, 
from  the  back  of  the  ulna  below  its  middle,  and  fleshy, 
from  the  interosseous  ligament.  It  adheres  to  the  ra- 
dius, and  terminates  in  a tendon  which  passes  through 
a groove  in  the  styloid  side  of  the  radius  along  with  the 
last  named  muscle. 

It  is  inserted  into  the  first  phalanx  of  the  thumb  by 
its  tendon,  which  is  extended  to  the  root  of  the  second 
phalanx. 

It  extends  the  first  phalanx. 

9.  The  Extensor  Major  Pollicis  Manus  arises, 
by  a small  tendinous,  and  extensive  fleshy  origin,  from 
the  back  of  the  ulna  above  its  middle,  and  from  the 
interosseous  ligament ; it  terminates  near  the  wrist  in  a 
tendon,  which  passes  through  a groove  on  the  back  of 
the  radius  near  the  ulna.  The  belly  of  this  muscle 
conceals,  very  much,  the  other  extensors  of  the  thumb. 

It  is  inserted,  by  its  tendon,  into  the  oblong  trans- 
verse tubercle  on  the  back  of  the  base  of  the  second 
phalanx  of  the  thumb. 

It  extends  the  second  phalanx. 

The  tendons  of  the  two  last  muscles  are  much  con- 


374 


OF  THE  UPPER  EXTREMITIES. 


nected  with  each  other,  and  are  spread  in  the  form  of  a 
membrane  on  the  back  of  the  thumb,  after  the  manner 
of  the  extensor  tendons  of  the  fingers. 

10.  The  Indicator  is  a small  muscle  on  the  back 
of  the  ulna,  concealed  by  the  extensor  communis  and 
extensor  ulnaris.  It  arises,  tendinous  and  fleshy,  from 
the  back  of  the  ulna,  commencing  near  its  middle,  and 
from  the  contiguous  part  of  the  interosseous  ligament. 
It  terminates  in  a tendon  which  goes  through  the  same 
fossa  with  the  extensor  communis;  it  afterwards  is 
joined,  about  the  head  of  the  first  phalanx,  to  the  ten- 
don of  the  common  extensor  belonging  to  the  fore- 
finger. 

With  the  tendon  of  the  extensor  communis  it  is  in- 
serted along  the  back  of  the  fore-finger  to  the  base  of 
the  third  phalanx. 

It  extends  the  fore-finger. 

At  this  stage  of  the  dissection  it  is  proper  to  notice 
the  Posterior  Carpal  Ligament,  which  passes  from  the 
side  of  the  radius  to  the  side  of  the  ulna.  It  is  two  in- 
ches in  breadth,  and  seems  much  like  a continuation  of 
the  fascia  of  the  fore-arm.  It  will  be  found  strongly 
attached  to  the  different  ridges  of  the  radius  and  ulna, 
and  from  its  want  of  elasticity,  perfectly  adapted  to 
prevent  the  tendons  from  springing  out  of  their  respec- 
tive grooves.  It  forms  one  jugum  for  the  two  first  ex- 
tensors of  the  thumb,  another  for  the  radial  extensors 


MUSCLES. 


375 


of  the  hand,  a third  for  the  tendon  of  the  third  exten- 
sor of  the  thumb,  a fourth  for  the  indicator  and  exten- 
sor communis,  and  a fifth  for  the  extensor  ulnaris. 

Of  the  Small  Muscles  of  the  Hand. 

The  skin  and  fat  being  carefully  removed  from  the 
palm  of  the  hand,  we  bring  into  view  the  Aponeuro- 
sis Palmaris.  This  is  a triangular  tendinous  mem- 
brane which  covers  all  the  hollow  of  the  hand,  and  is 
spread  over  its  muscles.  It  arises  from  the  anterior 
carpal  ligament  somewhat  narrow;  it  then  spreads  out, 
and  dividing  into  four  sections,  is  fixed  to  the  heads 
of  the  metacarpal  bones.  Each  section  bifurcates,  to 
allow  the  flexor  tendons  to  pass  to  the  fingers,  and  is 
I united  to  the  contiguous  sections  by  transverse  bands 
i or  frsena. 
i 

j The  Palmaris  Brevis  is  apt  to  be  cut  away  un- 
I consciously;  it  is  just  below  the  skin  at  the  inner  side 

I of  the  hand.  It  consists  of  separate  fasciculi  unequally 

I I divided,  and  arises  from  the  ligament  of  the  wrist,  and 
j from  the  ulnar  side  of  the  palmar  aponeurosis. 

I It  is  inserted  into  the  skin  and  fat  at  the  inner  mar- 
’ gin  of  the  hand,  and  covers  the  muscles  of  the  little 
finger. 

It  contracts  the  skin  of  the  hand. 

The  Aponeurosis  being  removed,  a good  view  is 


376 


OF  THE  UPPER  EXTREMITIES. 


obtained  of  the  flexor  tendons  and  many  of  the  small 
muscles  of  the  hand. 

The  Lumbricales  are  conspicuous;  they  are  four 
in  number,  of  the  size  and  shape  of  earth  worms. 
They  arise,  tendinous  and  fleshy,  from  the  radial  sides 
of  the  tendons  of  the  flexor  profundus,  beneath  the  li- 
gamentum  carpi  annulare,  and  a little  beyond  its  ante- 
rior edge. 

They  terminate  in  little  flat  tendons  which  run  along 
the  outer  or  radial  edges  of  the  fingers,  and  are  inser- 
ted into  the  tendinous  expansion  on  the  back  of  the 
first  phalanx  of  each  finger  about  its  middle. 

They  bend  the  first  phalanges. 

Four  muscles  constitute  the  ball  of  the  thumb. 

1.  The  Abductor  Pollicis  Manus  arises,  tendi- 
nous and  fleshy,  from  the  anterior  surface  of  the  liga- 
mentum  carpi  annulare  and  from  the  projecting  ends 
of  the  trapezium  and  scaphoides. 

It  is  inserted,  tendinous,  into  the  outer  side  of  the 
base  of  the  first  phalanx  of  the  thumb,  and  into  the 
tendinous  membrane  derived  from  the  extensors  on  its 
back  part. 

It  draws  the  thumb  from  the  fiugei’S.  This  muscle 
is  next  to  the  skin. 


2.  The  Opponens  Pollicis  is  beneath  the  abduc- 


MUSCLES. 


377 


tor,  and  without  its  removal  can  scarcely  be  seen.  It 
arises,  tendinous  and  fleshy,  from  the  projecting  point 
of  the  os  trapezium  and  from  the  adjacent  part  of  the 
annular  ligament. 

It  is  inserted,  tendinous  and  fleshy,  into  the  radial 
edge  of  the  metacarpal  bone  of  the  thumb  from  its  base 
to  its  head. 

It  draws  the  metacarpal  bone  inwards. 

3.  The  Flexor  Brevis  Pollicis  Manus  is  be- 
neath the  abductor  pollicis  and  at  the  ulnar  side  of  the 
opponens  pollicis.  A groove  is  formed  in'  it  by  the 
tendon  of  the  flexor  longus  pollicis,  which  divides  it 
into  two  heads. 

The  first  head  arises,  fleshy,  from  the  points  of  the 
trapezoides,  trapezium,  and  from  the  eontiguous  part 
of  the  internal  surface  of  the  annular  ligament,  and  is 
inserted  into  the  outer  sesamoid  bone ; the  sesamoid 
bone,  like  a patella,  being  connected  to  the  first  pha- 
lanx of  the  thumb  by  tendon. 

The  second  or  internal  head  arises,  fleshy,  from  near 
the  metacarpal  surfaces  of  the  magnum  and  unciforme, 
and  from  the  base  of  the  metacarpal  bone  of  the  middle 
finger.  It  is  inserted  into  the  inner  sesamoid  bone, 
which,  like  the  external,  is  connected,  by  ligament,  to 
the  first  phalanx. 

The  short  flexor,  as  its  name  implies,  bends  the  first 
joint  of  the  thumb. 

3 B 


378 


OF  THE  UPPER  EXTREMITIES. 


4.  The  Adductor  Pollicis  Maxus  lies  in  the 
palm  of  the  hand  beneath  the  lumbricales  and  the  ten- 
dons of  the  flexor  sublimis  and  profundus.  It  arises, 
fleshy,  from  the  ulnar  edge  of  the  metacarpal  bone  of 
the  second  finger  between  its  base  and  head. 

It  is  inserted,  tendinous,  into  the  inner  part  of  the 
base  of  the  first  phalanx  of  the  thumb  near  the  internal 
sesamoid  bone. 

It  pulls  the  thumb  towards  the  fingers. 

The  Abductor  Indicis  Manus  is  on  the  radial 
edge  of  the  hand  between  the  metacarpal  bones  of  the 
fore-finger  and  thumb,  and  is  just  beneath  the  skin. 
It  arises,  tendinous,  from  the  trapezium,  fleshy  from 
the  ulnar  edge  of  the  metacarpal  bone  of  the  thumb  be- 
tween its  base  and  head. 

Being  placed  along  the  side  of  the  metacarpal  bone 
of  the  fore-finger,  it  is  inserted,  by  a short  tendon,  into 
the  radial  side  of  the  first  phalanx. 

It  draws  the  fore-finger  from  the  others. 

There  are  three  muscles  constituting  the  fleshy  part 
of  the  ulnar  side  of  the  hand,  or  the  ball  of  the  little 
finger. 

1.  The  Abductor  Minimi  Dtgiti  Manus  is  tlie 
most  superficial.  It  arises,  fleshy,  from  the  protuber- 
ance on  the  internal  side  of  the  os  pisiforme  and  from 
the  contiguous  parts  of  the  annular  ligament. 

It  is  inserted,  tendinous,  into  the  ulnar  side  of  the 


MUSCLES. 


379 


iii’st  phalanx  of  the  little  finger  and  into  the  tendinous 
membrane  which  covers  its  back  part. 

It  draws  the  little  finger  from  the  rest. 

i 

2.  The  Flexor  Parvus  Minimi  Digiti  Manus  is 
beneath  the  abductor.  It  arises,  fleshy,  from  the 
unciform  process  of  the  os  unciforme,  and  from  the 
contiguous  parts  of  the  annular  ligament. 

It  is  inserted,  tendinous,  into  the  ulnar  side  of  the 
base  of  the  first  phalanx  of  the  little  finger,  being 
united  with  the  tendon  of  the  abductor,  and  with  the 
tendinous  membrane  expanded  over  the  back  of  the 
finger. 

It  bends  the  little  finger. 

The  Adductor  Metacarpi  Minimi  Digiti  is 
placed  beneath  the  Abductor  and  Flexor,  next  to  the 
metacarpal  bone.  It  arises,  fleshy,  from  the  unciform 
process  of  the  os  unciforme,  and  from  the  contiguous 
part  of  the  annular  ligament  of  the  wrist. 

It  is  inserted,  tendinous  and  fleshy,  into  the  fore 
part  of  the  metacarpal  bone  of  the  little  finger,  from  its 
base  to  its  head. 

It  brings  the  metacarpal  bone  of  the  little  finger  to- 
wards the  wrist,  and  thereby  deepens  the  hollow  of 
the  hand. 

The  Interosseous  Muscles  fill  up  the  interstices  of 
the  metacarpal  bones;  they  are  seven  in  number,  four 


380 


OF  THE  UPPER  EXTREMITIES. 


on  the  palm,  and  three  on  the  back  of  the  hand.  The 
latter  ones  arise  by  double  heads  from  the  contiguous 
sides  of  two  metacarpal  bones;  the  inner  ones  have  each 
a single  head  only,  which  comes  from  the  metacarpal 
bone  of  the  finger,  which  such  interosseous  muscle  is 
intended  to  serve.  As  a general  description  they  all 
may  be  said  to  arise,  fleshy  and  tendinous,  from  the 
base  and  sides  of  the  metacarpal  bones,  and  to  be  inser- 
ted tendinous,  into  the  sides  of  the  first  phalanges,  and 
into  the  tendinous  membranes  on  the  back  of  the  fin- 
gers, derived  from  the  tendons  of  the  extensor  com- 
munis. The  four  first  are  very  deeply  seated,  but  the 
three  others  rather  superficially. 

1.  The  Prior  Indicis  is  along  the  radial  side  of  the 
first  metacarpal  bone,  and  arises  from  the  base  and  side 
of  the  same. 

It  is  inserted,  tendinous,  into  the  radial  side  of  the 
first  phalanx. 

It  draws  the  fore-finger  towards  the  thumb. 

2.  The  Posterior  Indicis  is  at  the  ulnar  side  of 
the  first  metacarpal  bone.  It  arises  from  the  base  and 
ulnar  side  of  the  same  bone,  and  is  inserted,  tendinous, 
into  the  ulnar  side  of  the  first  phalanx  of  the  fore- 
finger. 

It  draws  the  fore-finger  towards  the  others. 


3.  The  Prior  Annularis  is  at  the  radial  side  of 


MUSCLES. 


381 


the  metacarpal  bone  of  the  third  or  ring  finger.  It 
arises  from  the  base  and  radial  side  of  the  said  bone. 

It  is  inserted,  tendinous,  into  the  radial  side  of  the 
first  phalanx  of  the  ring  finger. 

It  draws  that  finger  towards  the  thumb. 

4.  The  Interosseous  Digiti  Auricularis  is  at  the 
radial  side  of  the  metacarpal  bone  of  the  little  finger. 
It  arises  from  the  radial  side  and  base  of  said  bone. 

It  is  inserted,  tendinous,  into  the  radial  side  of  the 
first  phalanx  of  the  same  finger. 

It  draws  the  little  finger  towards  the  others. 

By  removing  the  tendons  of  the  extensor  communis 
from  the  back  T)f  the  hand,  we  see  the  three  posterior 
or  Rouble-headed  interosseous  muscles. 

5.  The  Prior  Medii  is  between  the  metacarpal 
bones  of  the  fore  and  middle  fingers.  It  arises  from 
the  opposite  roots  and  sides  of  these  bones. 

It  is  inserted  tendinous,  into  the  radial  side  of  the 
first  phalanx  of  the  middle  finger. 

It  draws  the  middle  finger  towards  the  thumb. 

6.  The  Posterior  Medii  is  between  the  metacar- 
pal bones  of  the  middle  and  ring  fingers.  It  arises, 
from  the  opposite  sides  and  roots  of  these  bones. 

It  is  inserted,  tendinous,  into  the  ulnar  side  of  the 
first  phalanx  of  the  middle  finger. 


382 


OF  THE  UPPER  EXTREMITIES. 


It  draws  the  middle  finger  towards  the  little. 

7.  The  Posterior  Annularis  is  between  the  me- 
tacarpal bones  of  the  ring  and  little  finger.  It  arises 
from  the  opposed  sides  and  roots  of  these  metacarpal 
bones. 

It  is  inserted,  tendinous,  into  the  ulnar  side  of  the 
first  phalanx  of  the  ring  finger. 

It  draws  the  middle  towards  the  little  finger. 


Section  IV. 

Of  the  Blood-  Vessds  of  the  Upper  Extremities, 

The  Arteries  of  the  Upper  Extremity  are  derived 
from  the  Subclavian,  the  course  of  which,  to  the  sca- 
leni  muscles,  is  described  in  the  account  of  the  neck. 
The  subclavian  passes  over  the  middle  of  the  first  rib 
between  the  scalenus  anticus  and  inedius  muscles,  and 
afterwards  goes  between  the  first  rib  and  the  subclavius 
muscle  to  the  arm-pit.  Here  it  is  called  Axillary  Ar- 
tery, (Arteria  Axillaris,)  and  its  position  is  under  the 
tendinous  insertion  of  the  pectoralis  minor,  and  almost 
touching  it;  it  then  passes,  at  the  internal  inferior  part 
of  the  head  of  tlie  humerus,  parallel  with,  and  border- 


BLOOD  VESSELS. 


383 


ing  on,  the  internal  edge  of  the  coraco  brachialis  mus- 
cle. At  the  posterior  fold  of  the  arm-pit  it  is  placed 
very  near  the  tendon  of  the  latissimus  dorsi,  between 
it  and  the  coraco  brachialis.  Emerging  from  the  axilla 
at  this  place,  its  name  is  changed  into  that  of  Arteria 
Brachialis. 

The  Arteria  Brachialis  descends  the  arm  at  the 
internal  margin  of  the  lower  part  of  the  coraco  brachi- 
alis, and  afterwards  at  the  internal  margin  of  the 
biceps  flexor  cubiti.  At  the  bend  of  the  arm  it  is  at 
the  inner  edge  of  the  tendon  of  the  biceps,  and  passes 
under  its  aponeurosis,  and  a little  below  the  joint  it 
splits  into  two  branches  of  nearly  equal  magnitude,  the 
Radial  and  the  Ulnar  Arteries. 

The  relative  situation  of  the  great  artery  with  the 
nerves  and  veins  of  the  part,  should  be  closely  observ- 
ed; between  the  scaleni  muscles,  the  majority  of  the 
nerves,  forming  afterwards  the  axillary  plexus,  is 
above  and  somewhat  posterior  to  the  subclavian  artery j 
but  when  this  artery  becomes  axillary,  the  nerves  unite 
in  various  combinations,  and  surround  it  like  so  many 
cords  of  a platted  whip  thong.  The  axillary  vein  is 
below  and  somewhat  in  front  of  the  artery,  and  very 
near  it.  These  several  parts  are  united  by  a loose, 
vascular,  adipose,  and  cellular  membrane  containing 
many  lymphatic  glands. 

1.  The  Arteria  Dorsalis  Superior  Scapula 
varies  much  in  its  origin;  it  comes  sometimes  from  the 
subclavian,  and  on  other  occasions  from  the  upper  part 


384 


OF  THE  UPPER  EXTREMITIES. 


of  the  axillary.  Not  unfrequently  it  is  a branch  of  the 
inferior  thyroid.  In  either  the  first  or  the  last  case, 
its  course  is  very  important  to  the  surgeon,  for  it  runs 
along  the  posterior  margin  of  the  clavicle  towards  its 
acromial  extremity,  and  in  an  operation,  by  being 
opened,  might  be  mistaken  for  the  subclavian  artery 
itself.  When  it  comes  from  the  axillary  artery  it  is 
tortuous,  and  has  to  ascend  to  its  destination,  being 
completely  out  of  the  way  of  an  operation  from  above, 
upon  the  subclavian  artery.  Its  final  distribution  is 
always  the  same,  for  it  passes  through  the  notch  in  the 
upper  costa  of  the  scapida,  and  there  divides  into 
branches  supplying  the  supra-spinatus  muscle  and  the 
shoulder  joint. 

2.  The  Arterije  Mammari^  Externa  arise  from 
the  axillary  just  above  the  pectoralis  minor.  They 
consist  in  four  principal  branches,  going  uniformly  to 
certain  parts;  but  the  origin  of  these  branches  varies, 
for  sometimes  they  are  originally  distinct  trunks  from 
the  axillary  artery,  and  on  other  occasions  blended  into 
one  or  more.  They  are 

a.  Thoracica  Superior,  distributed  to  the  parts  of 
the  pectoralis  major  muscle  just  below  the  clavicle, 
some  branches  going  to  the  pectoralis  minor. 

h.  Thoracica  Longa,  supplying  the  inferior  parts  of 
the  great  pectoral  muscle,  the  mamma,  and  integu- 
ments. 

c.  Thoracica  Acromialis,  making  for  the  fissure  be- 


BLOOD  VESSELS. 


385 


tween  tlie  deltoid  and  great  pectoral  muscle,  and  dis- 
tributed  to  them  along  the  margins  of  this  fissure 
upwards  and  do^vnwa^il. 

d.  Thoracica  Axillaris,  very  irregular  in  origin  and 
size;  when  small  it  is  distributed  generally  to  the  fat 
and  glands  of  the  axilla;  when  large  it  is  a trunk,  the 
size  of  a goose-quill,  running  on  the  scapular  surface 
of  the  serratus  major  anticus,  and  distributed  to  it  by 
branches  coming  off  at  right  angles. 

3.  The  ScAPULARis  arises  from  the  axillary  artery 
about  the  anterior  margin  of  the  subscapularis  muscle. 
It  passes  downwards  towards  the  ^ngle  of  the  scapula 
in  contact  with  this  muscle,  and  is  distributed  to  the 
teres  major  aiid  minor,  subscapularis  and  latissimus 
dorsi  muscles. 

A little,  below  the  neck  of  the  scapula  a large  trunk, 
the  Dorsalis  Inferior  Scapulas,  arises  from  the  scapula- 
ris,  which  winds  around  the  bone  to  be  distributed  to 
the  infraspinatus  and  the  contiguous  muscles,  an  anas- 
tomosis being  formed  under  the  neck  of  acromion  pro- 
cess, between  the  dorsalis  inferior  and  superior. 

4.  The  CiEcuiiFLEXA  Anterior  is  a small  artery 
about  the  size  of  a crow’- quill.  It  arises  from  the  ax- 
illary just  above  the  superior  or  posterior  margin  of 
the  tendon  of  the  teres  major  and  latissimus  dorsi.  It 
surrounds  half  the  os  humeri  just  below  its  head,  go- 
ing between  the  bone  and  the  coraco  brachialis  and 

3 c 


386 


OF  THE  UPPER  EXTREMITIES. 


biceps  muscle,  to  be  distributed  to  the  articulation  and 
to  the  contiguous  muscles.  ^ 

5.  The  CiRcuMFLEXA  Posterior  is  much  larger, 
and  arises  from  the  axillary  about  the  same  place  with 
the  last,  but  commonly  a little  below;  sometimes  they 
have  a-  common  trunk.  It  surrounds  the  back  part  of 
the  os  humeyi,  going  between  the  long  head  of  the 
triceps  and  the  bone  by  passing  between  the  teres 
minor  and  major  muscles  in  the  first  instance.  It  is 
distributed  to  the  shoulder  joint  and  the  contiguous 
muscles,  especially  the  deltoid. 

6.  Tlie  Profunda  Humeri  or  Spiralis  arises  from 
the  great  artery  of  the  upper  extremity  just  below  the 
tendon  of  the  teres  major,  where  the  artery  is  called 
Brachial  or  Humeral.  It  passes  downwards  a little  dis- 
tance, and  there  enters  the  interstice  between  the  first 
and  the  third  head  of  the  triceps  muscle.  It  winds 
between  this  muscle  and  the  bone  very  obliquely 
downwards,  and  appears,  at  last,  on  the  outer  side  of 
the  arm,  between  the  brachialis  internus  and  the  supi- 
nator longus;  it  reaches  to  the  external  condyle.  In 
this  course  the  profunda  sends  many  branches  to  the 
triceps  and  to  the  contiguous  muscles.  Its  origin  is 
sometimes  from  the  scapular  or  from  the  posterior  cir- 
cumflex artery. 


7.  The  Profunda  Minor  is  uncertain  in  its  origin, 


BLOOD  VESSELS. 


387 


4 

but  comes  commonly  from  the  humeral  two  inches  be- 
low the  last;  sometimes  it  is  a branch  of  the  last.  It 
is  distributed  on  the  internal  surface  of  the  triceps  ex- 
tensor, and  extends  to  the  internal  condyle. 

8.  The  Nutritia  is  a very  small  branch  from  the 
humeral,  arising  near  the  medullary  foramen  of  the  os 
humeri,  which  it  penetrates,  and  is  distributed  to  the 
lining  membrane. 

9.  The  Anastomotic  A is  a small  branch  from  the 
humeral,  arising  about  the  place  where  the  os  humeri 
begins  to  expand  in  order  to  form  the  elbow  joint.  It 
passes  on  the  internal  face  of  the  brachialis  internus 
muscle,  and  then  over  the  ridge  of  the  internal  con- 
dyle to  the  groove  between  the  condyle  and  the  ole- 
cranon process,  where  it  anastomoses  with  a recurrent 
branch  of  the  ulnar  artery. 

Several  arterioles  are  also  sent  from  the  humeral 
artery  to  the  biceps,  brachialis,  triceps;  and  coraco 
brachialis,  which  are  too  irregular  and  too  small  to  der 
serve  description. 

$ 

The  Humeral  Artery,  it  has  been  stated,  is  divid- 
ed a little  below  the  elbow  joint  into  two  principal 
trunks.  Radial  and  Ulnar.  Sometimes  this  division  is 
on  a line  with  the  joint;  at  other  times  it  occurs  nearer 
the  insertion  of  the  brachialis  muscle.  The  division^ 


388 


OF  THE  UPPER  EXTREMITIES. 


however,  does  occasionally  occur  in  all  the  space  be- 
tween the  axilla  and  the  elbow  joint,  in  w'hich  case 
the -radial  artery  sometimes  is  just  beneath  the  skin  at 
the  elbow,  and  continues  uncommonly  superficial  to  the 
wrist. 

The  Radial  Artery  (Radialis  Arteria)  in  the 
early  part  of  its  course,  is  at  the  bottom  of  the  fissure 
between  the  pronator  teres  and  the  supinator  radii  lon- 
gus;  afterwards  it  crosses  the  insertion  of  the  former, 
runs  parallel  with,  and  in  front  of  the  radius  to  the 
wrist,  between  the  tendons  of  the  supinator  longus  and 
of  the  flexor  radialis.  At  the  styloid  process  it  gets 
between  the  carpus  and  the  extensors  of  the  thumb, 
runs  a little  distance  on  the  radial  side  of  the  back 
of  the  hand,  and  then  penetrates  to  the  palm  between 
the  bases  of  the  metacarpal  bones  of  the  thumb  and  of 
the  fore-finger.  It  furnishes  the  following  branches, 
collateral  and  terminating. 

1.  The  Recurrens  Radialis  arises  about  the  neck  . 
of  the  radius.  It  winds  around  the  joint  externally, 
between  the  external  condyle  and  the  muscles  coming 
from  it,  and  anastomoses  with  the  spiralis  or  profunda 
of  the  humeral  artery,  being  distributed,  in  many  col- 
lateral branches,  to  the  joint  and  contiguous  muscles,  v 

2.  Several  small-  and  irregular  muscular  branches 


BLOOD  VESSELS. 


389 


arise  from  the  radial  artery  in  its  progress  to  the  wrist; 
they  have  no  appropriated  names. 

3.  The  SuPERFiciALis  VoLaE  arises  from  the  radial 
about  the  inferior  margin  of  the  pronator  cpiadratus 
muscle.  It  passes  superficially  over  the  process  of  the 
trapezium  to  the  muscles  of  the  ball  of  the'  thumb,  and 
one  of  its  terminating  branches  joins  the  arcus  subli- 
mis.  Sometimes  the  superficialis  volse  is  the  principal 
branch  of  the  radial. 

4.  The  Dorsalis  Carpi  arises  from  the  radialis  at 
the  carpus,  runs  transversely  across  the  back  of  the 
latter,  and  detaches  the  posterior  interosseous  arteries 
of  the  back  of  the  hand.  They  anastomose  with  bran- 
ches from  the  ulnar  and  interosseous  arteries  of  the 
fore-arm. 

5.  The  Magna  Pollicis,  a terminating  branch  of 
the  radial,  comes  from  it  in  the  palm  of  the  hand  just 

■ at  the  root  of  the  metacarpal  bone  of  the  thumb.  It 
runs  beneath  the  abductor  indicis,  and  at  the  head  of 
the  metacarpal  bone  divides  into  two  branches,  which 
run  along  the  sides  of  the  thumb  to  its  extremity,  where 
they  anastomose  and  terminate. 

6.  The  Radialis  Indicis,  arising  at  the  same  place 
; with  the  latter,  runs  along  the  metacarpal  bone  of  the 


390 


OF  THE  UPPER  EXTREMITIES. 


fore-finger,  and  along  the  radial  side  of  the  same  finger 
to  its  extremity. 

7.  The  Palmaris  Profunda  is  the  third  terminat- 
ing branch  of  the  radial  artery.  It  arises  near  the 
same  place  with  the  two  last;  crosses  the  hand  between 
the  metacarpal  bones  and  the  flexor  tendons,  thus  form- 
ing the  Arcus  Profundus,  from  which,  branches  pro- 
ceed to  the  interossei  muscles,  and  which  ends  on  the 
ulnar  side  of  the  palm  of  the  hand  by  a branch  to  tlie 
Arcus  Superficialis. 

The  Ulnar  Artery,  (Arteria  Ulnaris,)  one  of  the 
forks  of  the  brachial  at  the  elbow,  passes  more  in  a 
line  with  it  than  the  radial  artery  does.  Being  deeply 
seated,  it  goes,  immediately  after  its  origin,  urtder 
several  of  the  muscles  of  the  internal  condyle,  and  be- 
tween the  flexor  sublimis  and  profundus;  getting  from 
beneath  the  flexor  sublimis,  it  afterwards  runs  paral- 
lel with  the  ulna  or  nearly  so,  lying  on  the  flexor  pro- 
fundus between  the  flexor  ulnaris'  and  the  ulnar  mar- 
gin of  the  flexor  sublimis,  and  concealed  two-thij’ds  of 
the  way  down  the  fore-arm  by  the  overlapping  of  these 
muscles.  At  the  thin  part  of  the  fore-arm,  commonly 
called  the  wrist,  it  is  superficial,  and  may  be  felt  pul- 
sating in  the  living  body  at  the  radial  margin  of  the 
tendon  of  the  flexor  ulnaris. 

The  ulnar  artery,  at  the  carpus,  takes  a very  diffei' 
ent  course  from  the  radial,  for  it  passes  over  the  ante 


BLOOD  VESSELS. 


391 


rior  annular  ligament  of  tlie  carpus  just  at  the  radial 
side  of  the  os  pisiforrae,  to  which  it  is  held  by  a small 
ligamentous  noose,  and  then  proceeds  to  the  palm  of 
the  hand.  Between  the  aponeurosis  palmaris  and  the 
flexor  tendons  it  forms  that  curve  from  the  ulnar  to  the 
radial  side  of  the  hand  called  the  Arcus  Sublimis. 
This  curve  commonly  begins  a little  beyond  the  ante- 
rior margin  of  the  annular  ligament,  and  presenting  its 
convexity  forwards,  terminates  about  the  middle  of 
the  ball  of  the  thumb  at  its  inner  margin. 

The  branches  sent  from  the  ulnar  artery  are  as  fol- 
low: 

1.  The  Recuerens  Ulnaris  arises  from  the  ulnar 
about  the  lower  part  of  the  tubercle  of  the  radius,  and 
winding  upwards  is  distributed  in  small  branches  to 
the  muscles  of  the  internal  condyle.  One  of  its  ra- 
muscules  goes  between  the  internal  condyle  and  the 
olecranon  process,  to  anastomose  with  the  arteria 
anastomotica  of  the  humeral. 

2.  The  Interossea  arises  from  the  ulna  just  be- 
low the  other.  It  is  a large  trunk,  and  proceeds  but 
a little  distance  when  it  divides  into  two  principal 
branches  called  anterior  and  posterior  interosseal  ar- 
teries. 

a.  The  Interossea  Anterior  is  much  the  larger;  it 
runs  in  contact  with  the  interosseous  ligament  to  the 
upper  margin  of  the  pronator  quadratus,  giving  off' 


392 


OF  THE  UPPER  EXTREMITIES.  4 

branches  to  the  deep-seated  muscles  of  the  fore-arm 
in  its  course.  Under  the  pronator  it  perforates  the  in- 
terosseous  ligament,  and' distributes  to  the  back  of  the 
carpus  and  of  the  hand,  branches,  which  anastomose 
with  branches  of  the  radial  and  posterior  interosseal. 

b.  The  Interossea  Posterior  is  sometimes  a sepa-  • ^ 
rate  trunk,  arising  from  the  ulnar  just  above  the  for- 
mer. In  either  case  it  soon  perforates  the  interosseous  • . 
ligament  to  get  to  the  back  of  the  fore-arm.  Here  it  ?! 
sends  backwards  a Recurrent  Branch  to  the  back  of  ^ 
the  elbow,  which  anastomoses  with  the  recurrens  ul-  ’ . 
naris  and  radialis.  It  then  proceeds  downwards,  being  J 
dgeply  seated  tind  distributed  to  the  different  muscles 
on  the  back  of  the  fore-arm.  Some  of  its  branches,  \ 
as  was  mentioned,  reach  the  wrist,  and  anastomose  with  J 
the  carpal  arteries.  3 

i 

3.  The  ulnar  artery,  in  its  descent  on  the  fore-arm.  ^ 

sends  off  many  small  and  irregular  muscular  branches  m 
called  by  Professor  Chaussier,  Cubito-musculaires;  mi 
they  do  not  require  description.  • % 

4.  The  Dorsalis  Manus  leaves  the  ulnar  at  the 
lower  end  of  the  fore-arm,  and  passes  under  the  ten-  j 
don  of  the  flexor  ulnaris  to  the  back  of  the  hand.  It 
there  meets  ramuscules  of  the  radial  and  interosseous,  ^ 
and  conjointly  they  supply,  with  very  small  branches, 
the  back  of  the  wrist,  of  the  metacarpus  and  of  the 
fingers. 


BLOOD  VESSELS. 


393 


5.  As  the  Arcus  Superficialis  is  about  beginning, 
the  ulnar  artery  sends  superficial  but  small  branches 
to  the  integuments  of  the  palm.  And  a little  further 
on,  a considerable  branch,  which  dives  into  the  bottom 
of  the  palm,  through  the  muscles  of  the  little  ^ finger, 
and  joins  the  ulnar  extremity  of  the  arcus  profundus  ; 
this  is  the  Cubitalis  Manus  Profunda  of  Haller. 

6.  The  Arcus  Superficialis  then  sends  a branch 
to  the  ulnar  side  of  the  little  finger.  Afterwards  in  suc- 
cession three  digital  branches  are  sent  off,  which,  arriv- 
ing at  the  interstices  between  the  heads  of  the  metacar- 
pal bones,  each  divides  into  two  branches  to  supply  the 
sides  of  the  fingers  which  are  opposite  to  each  other ; one 
branch  is  called  Digito  radial,  the  other  Digito  ulnar, 
according  to  the  side  of  the  finger  on  which  the  artery 
may  be  placed. 

The  Digital  Arteries,  before  they  divide,  receive 
each  a small  branch  from  the  arcus  profundus.  The 
digito  radial  and  ulnar  arteries,  pass  along  the  front 
sides  of  the  fingers  to  their  extremities;  at  the  joints 
and  extremities,  anastomoses  between  the  arteries  of 
the  two  sides  of  the  same  finger  frequently  occur. 

The  Arcus  Superficialis  terminates  on  the  radial 
side  of  the  palm  by  a branch  which  joins  the  artery 
of  the  thumb  coming  from  the  radial. 

3 D 


394 


OF  THE  UPPER  EXTREMITIES. 


The  most  frequent  arrangement  of  the  arteries  of- 
the  hand  is  what  has  been  just  described;  anatomists 
are,  however,  not  all  agreed  on  this  point.  It  would 
probably  be  more  just  to  say,  judging  ft  om  our  eollec- 
tion  in  the  University,  that  this  oceurs  more  often  tlian 
any  other  single  arrangement.  The  variety,  in  fact, 
is  so  great,  that  before  a hand  is  opened  it  is  not  possi- 
ble to  know  in  what  manner  its  arteries  are  dis- 
tributed. Sometimes  the  radial  artery  furnishes  one- 
half  of  the  arcus  sublimis,  and  the  ulnar  the  other. 
On  other  occasions  the  interosseous  artei^y  is  continued 
as  a large  trunk  over  the  ligament  of  the  wrist,  and 
across  the  root  of  the  thumb  to  join  the  arcus  sublimis. 

Of  the  Veins  of  the  Upper  Extreinitics. 

These  Veins  are  abundantly  supplied  with  Aalvcs, 
and  are  superficial  and  deep-seated;  the  former  lying 
beneath  the  skin  have  original  names ; the  latter  atten- 
ding the  arteries,  on  all  occasions,  are  called  after 
them.  Anastomoses  are  numerous  in  both  sets,  but  are 
particularly  so  in  the  superficial,  where  plexuses  arc 
formed  which  surround  the  arm. 

Three  principal  superficial  trunks  are  formed  on  the 
lower  part  of  the  fore-arm,  one  on  its  radial  side,  an- 
other on  its  ulnar,  and  the  third  between  the  two. 

1.  The  Cephalic  A first  arises  about  the  root  of  the 
tliumb  and  fore-finger  on  the  back  of  the  hand;  a dis- 


BLOOD  VESSELS. 


395 


tiuct  trunk  is  formed  which  winds  obliquely  over  the 
radius,  and  then  runs  along  the  external  edge  of  the 
fore-arm  to  the  elbow  joint.  The  cephalic  ascends 
afterwards  along  the  external  edge  of  the  biceps  flexor 
muscle,  lies  over  the  interstice  between  the  pectoralis 
major  and  deltoid  muscles,  and  ascends  to  within  eight 
of  ten  lines  of  the  clavicle,  when  it  dips  into  the  axilla 
to  join  the  axillary  vein.  In  the  whole  of  this  coiu’se 
it  may  be  seen  easily  beneath  the  skin. 

2.  The  Vexa  Basilica  arises,  by  several  branches, 
from  tlie  back  of  the  hand,  principally  on  the  ulnar 
side,  one  of  which,  placed  between  the  metacarpal  bone 
of  the  little  finger  and  the  ring  finger,  is  called  Salvi- 
tella.  From  this  origin  the  basilic  vein  gets  to  the 
ulnar  side  of  the  fore-arm  and  continues  so  to  the  elbow 
joint,  receiving  on  either  side,  anterior  and  posterior 
ulnar  branches ; at  the  elbow  or  a little  above,  it  is  on 
the  inner  edge  of  the  biceps  muscle,  and  the  pulsation 
of  the  brachial  artery  may  be  felt  beneath  it.  It  as- 
cends regularly  at  the  inner  edge  of  the  biceps,  and 
about  the  middle  of  the  arm  becomes,  by  a junction 
with  other  veins,  the  Brachial  Vein. 

This  vein  on  the  fore-arm  frequently  consists  in  two 
trunks,  of  which  the  posterior  is  the  largest. 

3.  The  Vena  Mediana  arises,  by  branches,  from 
the  wrist  and  from  the  palm  of  the  hand;  it  forms  a 
trunk  in  the  front  of  the  fore-arm,  which,  three  or  four 


396 


OF  THE  UPPER  EXTREMITIES. 


inches  below  the  bend  of  the  arm,  bifurcates.  One 
branch,  the  Mediana  Cephalica,  joins  the  cephalic 
vein;  the  second,  the  Mediana  Basilica,  joins  the 
basilic  vein. 

The  deep-seated  Veins,  called  Vense  Satellites  or 
Comites,  are  found  in  company  with  every  artery  of 
the  upper  extremity,  there  being,  for  the  most  part, 
one  vein  to  each  side  of  the  artery.  They  anastomose 
frequently  by  branches  which  cross  the  artery.  At 
the  elbow,  the  radial,  ulnar,  and  interosseous  satellites 
unite,  and  form  a plexus  over  the  bifurcation  of  the 
brachial  artery;  from  which  plexus  a short  large 
branch  goes  outwards  to  join  one  of  the  superficial 
veins. 

The  trunk,  formed  by  the  union  of  the  satellites  of 
the  fore-arm,  passes  upwards  on  the  inner  side  of  the 
brachial  artery  and  receives  the  small  veins  from  the 
different  muscles.  Sometimes  it  joins  the  basilic 
about  the  middle  of  the  humerus;  on  other  occasions 
it  joins  it  near  or  in  the  axilla,  from  which  union  re- 
sults the  axillary  vein. 

The  Vena  Axillaris  receives  the  veins  corres- 
ponding with  the  circumflex,  scapular,  and  thoracic 
arteries,  in  their  proper  succession.  It  is  fixed  be- 
neath the  artery  and  very  near  it  in  the  same  sheatli 
of  cellular  substance.  Under  the  clavicle  it  becomes 


NERVES. 


397 


Vena  Subclavia;  and  as  sueh  it  passes  between  the  cla- 
vicle and  the  first  rib  at  the  inner  side  of  the  subcla- 
vian artery.  It  then  leaves  the  artery  to  go  in  front 
of  the  scalenus  anticus,  whereas  the  artery  goes  be- 
tween this  muscle  and  the  medius.  After  crossing  the 
first  rib  it  receives  the  superior  dorsal  vein  of  th-s  sca- 
pula, the  external  jugular,  and  afterwards  the  internal 
jugular,  besides  several  small  veins  from  the  skin  and 
muscles  of  the  neck. 


Section  V. 

Of  the  JVerves  of  the  Upper  Extremities. 

The  four  inferior  cervical  and  the  first  dorsal  nerves 
supply  the  upper  extremity  by  an  appropriation  of 
nearly  the  whole  of  their  anterior  branches,  which 
are  of  considerable  magnitude,  especially  the  three 
intermediate  ones.  They  come  out  between  the  an- 
terior and  the  middle  scalenus  muscle,  being  situated 
above  and  posterior  to  the  subclavian  artery,  at  vari- 
ous heights  according  to  the  origin  of  the  nerve  indi- 
vidually. Almost  immediately  after  disengaging  them- 
selves from  the  scaleni  muscles,  they  commence  the 
formation  of  a plexujs  which  surrounds  the  artery  and 


398 


OF  THE  UPPER  EXTREMITIES. 


continues  with  it  to  the  lower  part  of  the  axilla.  The 
fourth  and  fifth  cervical  nerves  unite  into  a common 
trunk  which  splits  into  two;  the  seventh  cervical  and 
the  first  dorsal  do  the  same ; the  sixth  cervical  also  bi- 
furcates. It  is  under  various  combinations  of  these 
different  primary  divisions  that  the  axillary  plexus  is 
formed,  from  which  proceeds  the  different  nerves  of 
the  upper  extremity.  This  plexus,  from  its  close  con- 
nexion with  the  great  artery,  must,  of  course,  go  be- 
tween the  subclavius  muscle  and  the  first  rib;  and,  in 
the  upper  part  of  the  axilla,  separate  the  axillary  vein 
from  the  artery  in  some  measure.  The  following  bran- 
ches are  given  off  by  the  brachial  plexus,  besides  the 
filaments  fwm  its  roots  to  the  sympathetic  and  phrenic 
in  front,  already  mentioned  in  the  account  of  the  Neck. 

1.  The  Nervus  Scapularis  is  a small  branch  com- 
ing from  the  upper  part  of  the  plexus,  commonly  the 
fourth  cervical  nerve.  It  accompanies  the  arteria  dor- 
salis scapulee  superior  to  the  foramen  in  the  upper  costa 
of  the  scapula,  and  is  distributed  to  the  muscles  on  the 
back  of  the  scapula. 

2.  The  Nervi  Thoracici  are  priin,arily  two  or 
three  in  number.  They  arise  from  the  middle  of  the 
plexus,  and  are  divided  into  anterior  and  posterior 
branches,  the  former  being  distributed  upon  the  pec- 
toralis  major  and  minor,  the  latter  upon  the  serratus 
major  anticus. 


NERVES.  399 

3.  The  Nervi  Subscapulares  of  Bichat  are  about 
three  in  number ; they  com«  also  from  the  central  parts 
of  the  plexus  to  be  distributed  upon  the  teres  major; 
latissimus  dorsi;  and  subscapularis. 

■ 4.  The  Nervus  Axillaris,  or  Circumflexus, 
comes  from  the  lower  part  of  the  brachial  plexus.  It 
follows  the  course  of  the  posterior  circumflex  artery, 
winding  around  the  upper  part  of  the  os  humeri  be- 
tween the  teres  minor  and  major  in  order  to  get  to  the 
internal  surface  of  the  deltoid  muscle,  where  it  termi- 
nates. In  its  passage  it  also  furnishes  branches  to  the 
subscapularis,  the  teres  major  and  minor,  the  infra- 
spinatus, and  to  the  integuments  on  the  back  of  the 
shoulder  and  arm.* 

5.  The  Nervus  Cutaxeus  Ixterxus  proceeds 
from  the  lower  part  of  the  brachial  plexus,  and  follows 
the  course  of  the  basilic  vein  to  the  elbow  or  near  it. 
In  its  descent  it  detaches  small  cutaneous  filaments  an- 
teriorly to  the  integuments  of  the  biceps,  and  poste- 
riorly to  those  of  the  triceps.  A little  above  the  bend 
of  the  elbow,  commonly  where  the  median  basilic  joins 
the  basilic  vein,  it  divides  into  two  terminating  bran- 
ches of  nearly  equal  magnitude.  The  one  next  the 
internal  condyle  lies  in  front  of  the  basilic  vein  just  at 
its  junction  with  the  median  basilic,  and  continues  in 
front  and  parallel  with  it  for  some  inches.  It  is  dis- 
tributed, by  many  ramifications,  to  the  skin  of  the 


400 


OF  THE  UPPER  EXTREMITIES. 


ulnar  side  of  th?  fore-arm  and  back  of  the  hand,  some 
of  the  branches  winding  around  to  the  back  part  of 
the  fore-arm.  The  other  branch  of  the  internal,  cutane- 
ous passes  beneath  the  median  basilic  vein  about  six 
lines  from  its  junction  with  the  basilic,  and  is  distri- 
buted to  the  integuments  on  the  middle  front  of  the 
fore-arm.  Before  this  latter  branch  reaches  the  me- 
dian basilic  vein  it  sends  off  a cutaneous  filament  which 
Crosses  the  median  basilic  in  front,  about  half-way  in 
the  course  of  this  vein. 

6.  The  Nervus  Musculo  Cutaxeus  comes  from 
the  middle  of  the  brachial  plexus.  It  perforates  ob- 
liquely the  upper  part  of  the  coraco- brachial  is  muscle, 
to  which  it  dispenses  filaments,  it  then  passes  between 
the  biceps  and  brachialis  internus  muscles,  giving  also 
filaments  to  both  of  them.  Its  course  being  remark- 
ably oblique  under  the  biceps  muscle,  it  makes  its  ap- 
pearance superficially,  only  a little  above  the  elbow 
joint  near  the  external  condyle.  It  then  passes  super- 
ficially between  the  skin  and  the  supinator  radii  lon- 
gus  muscle,  distributing  filaments  in  its  course,  and 
near  the  lower  part  of  the  radius  djndes  into  two  or- 
ders of  fibres,  one  of  which  is  distributed  on  the  pal- 
mar side  of  the  hand,  and  the  other  on  the  dorsal,  but 
both  go  to  the  integuments. 

7.  The  Nervus  Radialis,  or  Musculo  Spiralis, 
arises  from  the  upper  portion  of  the  brachial  plexus. 


NERVES. 


401 


It  is  a large  trunk  which  winds  spirally  around  the 
os  humeri  between  the  triceps  muscle  and  the  bone, 
entering  the  fissure  between  the  third  and  the  first 
head  of  the  triceps.  It  appears  on  the  outside  of  the 
os  humeri  between  the  brachialis  internus  and  the  tri- 
ceps muscles,  running  for  some  inches  in  contact  with 
their  intermuscular  ligament.  While  beneath  the  tri- 
ceps it  sends  several  branches  to  its  heads.  There  are 
three  principal  trunks  afterwards  to  this  nerve. 

a.  The  Ramus  Superficialis  Dorsalis  is  sent  from  it 
on  a line  with  the  point  of  the  deltoid  muscle.  This 
branch,  then,  goes  just  below  the  skin,  parallel  with 
and  over  the  external  ridge  of  the  os  humeri;  it  of 
course  crosses  the  origin  of  the  muscles  of  the  exter- 
nal condyle.  It  continues  superficial  on  the  posterior 
external  edge  of  the  supinator  radii  longus  muscle, 
and  terminates  in  the  integuments  on  the  back  of  the 
hand. 

The  continued  trunk  of  the  muscular  spiral  goes  in 
the  interstice  between  the  extensor  muscles  and  the 
brachialis  internus,  and  at  the  external  condyle  divides 
into  the  other  two  branches,  from  which  filaments  pro- 
ceed to  the  contiguous  heads  of  the  muscles. 

b.  The  Ramus  Profundus  Dorsalis,  perforates  the 
supinator  brevis  muscle,  and  gets  beneath  the  radial 
extensors  to  the  back  of  the  fore-arm;  it  is  then  dis- 
tributed in  numerous  filaments  to  the  muscles  on  the 
back  of  the  fore-arm,  some  of  its  branches  reaching  to 
the  wrist. 

3 E 


402 


OF  THE  UPPER  EXTREMITIES. 


c.  The  Ramus  Superficialis  Anterior  seems  to  be  a 
continuation  of  the  main  trunk  of  the  nerve,  and  de- 
scending at  the  anterior  margin  of  the  supinator  radii 
longus  muscle,  it  joins  with  the  radial  artery  and  con- 
tinues in  its  company  to  a short  distance  below  the 
middle  of  the  radius.  Here  it  crosses  the  bone  ob- 
liquely beneath  the  tendon  of  the  supinator  longus, 
and  then  divides  into  a palmar  and  a dorsal  ramuscule; 
the  first  being  distributed  to  the  muscles  and  integu- 
ments of  the  thumb,  the  second  terminating  so  as  to 
supply  the  back  of  the  hand,  of  the  thumb,  fore, 
middle,  and  ring  fingers  to  their  extremities. 

8.  The  Nervus  Medianus  arises  from  the  brachial 
plexus,  like  the  other  nerves.  It  descends  the  arm  at 
the  inner  edge  of  the  biceps  muscle  along  the  anterior 
surface  of  the  humeral  artery,  adhering  firmly  to  it 
and  to  the  deep-seated  veins  by  cellular  substance.  As 
far  as  the  elbow  it  sends  off*  no  branch  of  importance. 
There,  it  lies  at  the  side  of  the  biceps  tendon,  crosses 
the  lower  part  of  the  brachialis  internus,  and  being  be- 
neath the  aponeurosis  of  the  biceps.  It  then  perforates 
the  pronator  teres  and  gets  between  the  flexor  subli- 
mis  digitorum,  and  the  flexor  longus  pollicis,  and 
enters  the  palm  of  the  hand  under  the  ligamentum 
carpi  at  the  radial  edge  of  the  tendons  of  the  flexor 
sublimis.  In  the  palm  it  is  situated  beneath  the  apo- 
neurosis and  the  arcus  sublimis. 

The  median  nerve  dispenses  the  following  branches- 


NERVES. 


403 


At  the  bend  of  the  arm  it  furnishes  filaments  to  the 
heads  of  the  first  layer  of  muscles  of  the  fore-arm; 
and  a little  below,  it  detaches  the  nervus  interosseus 
which  supplies  filaments  to  the  flexor  longus  pollicis 
and  flexor  profundus.  The  interosseous  nerve  then 
descends  with  the  interosseous  artery  in  front  of  the 
interosseous  ligament,  and  terminates  in  the  pronator 
quadratus.  Before  the  median  nerve  reaches  the 
wrist  it  sends  a branch  which  supplies  with  filaments 
the  muscles  and  integuments  of  the  ball  of  the  thumb. 
In  the  palm  of  the  hand  it  divides  and  subdivides,  so 
as  to  furnish  the  two  sides  of  the  thumb,  of  the  fore,  of 
the  middle,  and  one  side  of  the  ring  finger  with 
branches,  which  reach  their  extremities  along  with  the 
digital  arteries. 

9.  The  Nervus  Ulnaris  comes  from  the  lowest 
section  of  the  brachial  plexus.  It  descends  along  the 
internal  anterior  part  of  the  triceps  muscle  in  a groove 
formed  between  it  and  the  intermuscular  ligament, 
diverging  in  this  course  gradually  from  the  median 
nerve  till  it  reaches  the  elbow,  when  it  is  at  its  greatest 
point  of  separation.  At  the  elbow  it  is  behind  the 
internal  condyle,  in  the  groove  between  it  and  the 
olecranon,  and  separates  the  two  heads  of  the  flexor 
ulnaris  muscle.  It  then  gets  to  the  fore-arm  between 
this  muscle  and  the  flexor  profundus  digitorum,  and 
continues  between  them  to  within  two  inches  of  the 
wrist  joint,  when  it  detaches  the  Ramus  Dorsalis. 


404 


OF  THE  UPPER  EXTREMITIES. 


The  Ramus  Dorsalis  slips  between  the  ulna  and  the 
tendon  of  the  flexor  ulnaris,  runs  along  the  internal 
margin  of  the  ulna  to  the  carpus,  when  it  divides  into 
ramuscules  which  supply  the  ulnar  side  of  the  integu- 
ments on  the  back  of  the  hand  and  the  backs  of  the 
two  last  fingers.  At  the  interval  between  the  heads 
of  the  metacarpal  bones  of  the  middle  and  ring  fingers, 
a considerable  ramuscule  joins  one  from  the  ramus  su- 
perficialis  anterior  of  the  nervus  radialis  or  musculo 
spiralis. 

The  Ulnar  Nerve,  having  given  off  this  dorsal 
branch,  descends  along  the  radial  margin  of  the  ten- 
don of  the  flexor  ulnaris  and  of  the  os  pisiforme  above 
the  annular  ligament  to  the  palm  of  the  hand.  Get- 
ting beneath  the  aponeurosis,  it  there  detaches  first  a 
deep-seated  branch,  which  penetrates  the  muscles  of 
the  little  finger  to  supply  them,  the  interossei,  and  the 
short  flexor  of  the  thumb.  The  ulnar  nerve  then 
furnishes  a superficial  branch,  and  afterwards  divides 
into  three ; one  for  the  ulnar  side  of  the  little  finger, 
another  for  the  opposing  sides  of  the  little  and  ring 
finger,  and  a third  which  joins  the  most  internal  digi- 
tal branch  of  the  median  nerve. 

To  conclude;  the  dissector  should  also  attend  to 
what  are  called  the  Intercosto-Humeral  Nerves. 
They  consist  of  a branch  from  the  second,  and  anotlier 
from  the  third  intercostal,  which  pass  out  at  the  fore 
and  lateral  parts  of  the  thorax;  the  first  from  beneath 


NERVES. 


405 


the  second  rib,  and  the  other  from  beneath  the  third 
rib. 

The  first  intercosto-humeral,  being  connected  with 
a filament  from  the  internal  cutaneous,  is  distributed 
upon  the  axillary  glands,  and  the  integuments  of  the 
axilla  and  inner  side  of  the  arm.  The  second,  being 
joined  by  filaments  from  the  first,  is  chiefly  distributed 
to  the  integuments  on  the  back  of  the  arm,  some  of  its 
branches  reaching  the  elbow.  The  numbness  of  the 
inner  side  of  the  arm,  in  angina  pectoris,  is  supposed 
to  be  owing  to  the  sympathy  of  these  nerves  with  the 
cardiac. 


PART  III. 


CHAPTER  II. 

Of  the  Lower  Extremitien. 


Section  I. 

• Of  the  Fascia. 

The  lower  Extremity,  from  the  pelvis  to  the  foot, 
is  enveloped  by  a strong  Fascia  or  Tendinous  Mem- 
brane, lying  between  the  skin  and  the  muscles.  This 
fascia  consists,  for  the  most  part,  of  ligamentous  fibres, 
passing  in  the  direction  of  the  length  of  the  limb, 
secured  together  by  transverse  filaments  of  the  same 
matter,  but  by  no  means  so  abundant.  Its  structure 
undergoes  some  variations;  its  greater  part  is  decidedly 
of  the  character  just  mentioned;  but  at  the  groin  it  is 
between  ligament  and  cellular  membrane;  the  latter 
occasionally  predominates  so  much,  that  the  appearance 
of  the  first  is  lost,  particularly  in  corpulent  subjects. 


FASCIA. 


407 


On  the  contrary,  in  the  lean  and  such  as  have  suffered 
from  pressure  and  irritation  of  the  part  by  hernial  pro- 
trusion, the  ligamentous  structure  is  welP  expressed. 
On  the  Gluteus  Maximus  also,  this  fascia  exists  as  a 
condensed  cellular  membrane,  sending  in  its  processes 
between  the  fasciculi  of  the  muscle. 

The  thickness  of  the  Fascia  Femoris  is  not  uniform. 
On  the  outer  side  of  the  thigh,  knee,  and  hip,  it  is 
very  thick  and  strong;  on  the  inner  side  it  is  thin,  and, 
compared  with  the  other,  weak.  It  is  thick  on  the 
anterior  part  of  the  leg,  and  somewhat  thinner  on  the 
posterior,  but  in  neither  is  it  so  thick  as  at  the  outer 
part  of  the  thigh.  At  the  ancle  it  is  connected  with 
the  bony  prominences  around  .it,  and  increasing  in 
thickness,  it  constitutes  the  annular  ligament  of  the 
joint  for  confining  the  tendons  on  its  anterior  part. 
It  is  also  extended  over  the  foot,  and  is  connected  at 
different  points  to  its  periphery  so  as  to  keep  itself 
tense. 

This  membrane  is  very  closely  attached  to  the  cel- 
lular membrane  at  every  point  of  its  external  surface, 
and  is  kept  tense  all  over  by  its  bony  connexions. 
Above,  it  arises  from  the  exterior  margin  of  the  pelvis, 
as  constituted  by  the  pubes,  Poupart’s  ligament,  the 
crista  of  the  ilium,  the  side  of  the  sacrum  and  the 
ischium.  At  the  knee  it  is  fastened  to  the  condyles 
of  the  os  femoris,  and  to  the  heads  of  the  tibia  and 
fibula.  On  the  posterior  part  of  the  thigh  it  sends  in 
a long  process,  by  which  it  adheres  to  the  linea  aspera. 


408 


OF  THE  LOWER  EXTREMITIES. 


Its  connexion  with  the  knee  and  ancle,  below,  fixes  it 
on  the  leg;  besides  which  it  adheres  to  the  spine  of  the 
tibia. 

Its  connexion  with  the  muscles  of  the  lower  extre- 
mity is  very  interesting ; to  some  of  them  it  adheres  by 
its  internal  face,  and  to  others  it  does  not.  To  the 
muscles  of  the  hip  it  adheres  closely,  and  gives  origin 
to  some  of  the  fibres  of  the  gluteus  medius.  To  the 
muscles  of  the  exterior  face  of  the  thigh  its  adherence 
is  generally  loose,  and  indeed  in  some  parts  scarcely 
deserves  to  be  considered  as  such,  as  where  the  inter- 
nal surface  of  the  fascia  is  opposed  to  the  tendinous 
facing  of  the  vastus  externus  muscle.  On  the  internal 
semicircumference  of  the  thigh,  it  adheres  somewhat 
closely  to  the  muscles  by  cellular  membrane.  On  the 
leg  it  is  in  close  connexion  with  the  muscles  of  its  an- 
terior and  fibular  side,  many  of  their  fibres  arising  from 
it;  but  on  the  posterior  face  of  the  leg  it  is  rather 
loosely  fixed  to  them.  From  the  internal  face  of  the 
fascia,  prolongations  of  cellular  membrane  of  various 
densities,  sometimes  ligamentous,  are  sent  in  between 
most  of  the  muscles.  These  prolongations  separate 
the  muscles  from  each  other,  form  sheaths  in  which 
they  repose,  and  preserve  them  in  their  position  in 
some  instances.  As  an  envelope  to  the  muscles  of  the 
leg  the  fascia  is  highly  useful  in  supporting  and  sus- 
taining their  action.  The  knowledge  of  its  peculiar 
connexion  at  different  parts  of  the  lower  exti’emity. 


MUSCLES. 


409 


is  all  important  in  the  management  of  abscesses  of  that 
region. 

Though  useful,  it  is  not  indispensable  to  make  a 
complete  investigation  of  the  fascia  at  once,  but  the  cir- 
cumstances mentioned  should  be  very  carefully  ob- 
served in  extending  downwards  the  muscular  dissec- 
tion. 


Section  II. 

Of  the  Muscles  of  the  Lower  Extremities. 

1 

The  Psoas  Magnus,  Psoas  Parvus  and  Iliacus 
Internus  are  described  at  pages  257,  258. 

The  Sartorius  arises,  by  a short  tendon,  from  the 
anterior  superior  spinous  process  of  the  ilium ; a body 
of  various  breadths  in  different  subjects  is  then 
formed,  whose  fibres  are  in  the  direction  of  its  length. 
It  passes  in  a spiral  course  to  the  inner  side  of  the 
thigh  and  the  internal  condyle,  and,  winding  under 
the  head  of  the  tibia,  advances  forwards  so  as  to  be 
inserted  into  the  side  of  the  lower  part  of  its  tubercle 
by  a broad  tendon.  The  lower  part  of  the  tendon  is 

3 F 


410 


- OF  THE  LOWER  EXTREMITIES. 


continued  into  the  fascia  of  the  leg,  by  which  this 
muscle  is  preserved  in  its  spiral  direction. 

The  sartorius  muscle  is  superficial,  lying  its  whole 
course  immediately  beneath  the  fascia  femoris;  it  cros- 
ses  the  rectus  femoris,  vastus  internus,  and  triceps 
abductor;  at  the  lower  part  of  the  thigh,  just  above 
the  knee,  it  is  between  the  tendon  of  the  latter  and 
that  of  the  gracilis. 

It  bends  the  leg  and  draws  it  obliquely  inwards. 

The  Tensor  Vaginje  Femoris  is  a short  muscle 
just  on  the  outer  side  of  the  origin  of  the  sartorius ; it 
arises,  tendinous,  from  the  anterior  superior  spinous 
process  of  the  ilium,  and  passes  downwards  and  some- 
what backwards  between  two  laminge  of  the  fascia 
femoris. 

It  is  inserted,  a little  below  the  level  of  the  trochan- 
ter major,  into  the  inner  face  of  the  fascia  femoris. 
It  rotates  the  foot  inwards,  and  makes. the  fascia  tense. 

The  Rectus  Femoris  is  in  front  of  the  thigh  bone 
and  just  beneath  the  fascia  femoris.  It  is  a complete 
penniform  muscle,  fleshy  in  front  for  the  most  part, 
but  faced  behind  with  tendon.  It  arises,  by.  a round 
tendon,  from  the  anterior  inferior  spinous  process, 
which  is  joined  by  another  tendon  coming  from  the 
superior  margin  of  the  acetabulum. 

It  is  inserted  into  the  superior  surface  of  the  patella 


MUSCLES. 


411 


by  a strong  tendon,  and  intermediately  by  the  liga- 
mentiim  patellae  into  the  tubercle  of  the  tibia. 

It  extends  the  leg. 

Under  the  rectus  femoris,  the  anterior  and  lateral 
parts  of  the  thigh  bone  are  enveloped  by  a large  mus- 
cular mass,  considered,  by  most  anatomists,  as  three 
distinct  muscles,  called  Vastus  Externus,  Vastus  Inter- 
nus,  and  Crurseus  or  Cruralis.  Their  heads  are  very 
distinguishable  from  each  other,  but  below  they  are 
inseparably  united  and  join  with  the  patella. 

The  Vastus  Externus,  a very  large  muscle  on 
the  outside  of  the  thigh,  arises,  tendinous  and  fleshy, 
from  the  upper  part  of  the  os  femoris  immediately  b*e- 
low  the  trochanter  major.  Its  origin  commences  in 
front,  and  passes  obliquely  around  the  bone  to  the 
linea  aspera.  It  continues,  afterwards,  to  arise  the 
whole  length  of  the  linea  aspera,  and  from  the  upper 
half  of  the  line  running  from  it  to  the  external  condyle. 

It  fibres  pass  inwards  and  downwards,  and  are  inser- 
ted, by  a flat  tendon,  into  the  external  edge  of  the 
tendon  of  the  rectus,  and  also  into  the  external  upper 
part  of  the  patella.  This  muscle  has  a broad  tendi- 
nous surface  exteriorly  and  above ; at  its  lower  part  it 
has  a tendinous  facing  on  the  side  next  to  the  bone. 

It  also  extends  the  leg. 


The  Vastus  Internus  covers  the  whole  inside  of 


412 


OF  THE  LOWER  EXTREMITIES. 


the  os  femoris.  It  arises,  by  a fleshy  and  pointed  ori- 
gin, in  front  of  the  os  femoris  just  on  a level  with  the 
trochanter  minor,  tendinous  and  fleshy,  from  the  whole 
length  of  the  internal  edge  of  the  linea  aspera,  and  from 
the  line  leading  from  it  to  the  internal  condyle. 

It  fibres  descend  obliquely,  and  are  inserted  by  a flat 
tendon  into  the  internal  edge  of  the  tendon  of  the  rec- 
tus, and  into  the  upper  internal  edge  of  the  patella. 

It  also  extends  the  leg. 

The  Crurx^us  Muscle  is  almost  completely  over- 
lapped and  concealed  by  the  two  vasti,  and  is  imme- 
diately behind  the  rectus  femoris.  The  edge  of  the 
vastus  externus  above  is  very  distinguishable  from  it, 
as  it  overlaps  it,  and  is  rounded  ofi*,  besides  being 
somewhat  separated  by  vessels.  But  the  origin  of  the 
eruraeus  on  the  side  of  the  vastus  internus  is  not  so 
distinct,  as  the  fibres  of  the  two  muscles  run  to- 
gether; it  is  therefore  necessary  most  frequently 
to  cut  through  some  of  the  fibres  on  the  internal  face 
of  the  os  femoris  on  a level  with  the  trochanter  minor. 
The  crurseus  will  then  be  seen  to  arise,  fleshy,  from 
all  the  fore  part  of  the  bone,  and  from  all  its  outside 
as  far  as  the  linea  aspera.  Between  the  internal  edge 
of  this  muscle  and  the  linea  aspera,  the  interior  face 
of  the  os  femoris  is  naked,  for  an  inch,  along  the  whole 
shaft  of  the  bone,  which  is  very  readily  seen  by  turn- 
ing off  the  vastus  internus. 

The  Cruraaus  is  inserted  into  the  posterior  face  of 


MUSCLES. 


413 


the  tendon  of  thfe  rectus  below,  and  into  the  upper  sur- 
face of  the  patella.  It  also  extends  the  leg. 

The  Ligaraentum  Patellae  is  the  common  cord  by 
which  the  action  of  the  four  last  named  muscles  is 
communicated  to  the  tibia.  It  is  a flattened  thick 
tendon  an  inch  and  a half  wide,  arising  from  the  in- 

I 

ferior  edge  of  the  patella,  and  inserted  into  the  tuber- 
cle of  the  tibia.  Besides  this,  a fascia  or  tendinous 
expansion  comes  from  the  inferior  ends  of  these  mus- 
cles, and  extends  itself  over  the  whole  of  the  an- 
terior and  lateral  parts  of  the  knee  joint,  and  is  insert- 
ed into  the  head  of  the  tibia  and  of  the  fibula.  Through 
this  it  happens  that  even  when  the  patella  or  its  tendon 
is  fractured,  some  motion  or  extension  may  be  com- 
municated to  the  leg  from  the  thigh. ^ 

The  Gracilis  is  a beautiful  muscle  at  the  inner 
margin  of  the  thigh,  which  lies  immediately  under  the 
fascia,  and  extends  from  the  pelvis  to  the  leg. 

It  arises,  by  a broad  thin  tendon,  from  the  front  of 
the  os  pubis  just  at  the  lower  part  of  its  symphysis, 
and  from  its  descending  ramus ; the  muscle  tapers  to  a 
point  below,  and  a little  above  the  knee  terminates  in 
a round  tendon  which  passes  behind  the  internal  con- 
dyle of  the  os  femoris  and  the  head  of  the  tibia.  It 
then  makes  a curve  forwards  and  downwards  at  the  in- 

A case  of  this  kind  was  lately  in  tlie  Philadelphia  Alms- 
house. 


414 


OF  THE  LOWER  EXTREMITIES. 


ternal  side  of  the  latter,  and  is  inserted  at  the  lateral 
and  inferior  part  of  its  tubercle. 

The  tendon  at  the  knee  is  beneath  the  tendon  of 
the  sartorius.  This  muscle  is  a flexor  of  the  leg. 

The  Pectinalis  is  a short  fleshy  muscle  at  the 
inner  edge  of  the  psoas  raagnus.  It  arises,  fleshy, 
from  the  concavity  on  the  upper  face  of  the  pubes 
between  its  erista  and  the  ridge  above  the  obturator 
foramen,  and  is  inserted,  tendinous,  into  the  linea  aspera 
immediately  below  the  trochanter  minor. 

It  draws  the  thigh  inwards  and  forwards. 

The  Triceps  Adductor  Femoris  is  a large  mus- 
cular mass  consisting  of  three  distinct  portions,  which 
are  placed  at  the  inner  side  of  the  thigh,  and  contii- 
bute  much  to  fill  up  the  vacuity  between  the  thigh 
bones  above.  These  portions  are 

1.  The  Adductor  Longus  which  comes,  by  a round- 
ed short  tendon,  from  the  upper  front  part  of  the  pubes 
near  its  symphysis;  it  forms  a triangular  belly  which 
increases  in  breadth  in  its  descent,  and  is  inserted 
into  the  middle  third  of  the  linea  aspera  at  its  inner 
edge*. 

This  muscle,  as  the  subject  lies  on  its  back,  is  up- 
permost of  the  three ; its  origin  is  between  that  of  the 
pectinalis  and  of  the  gracilis;  its  upper  edge  is  in  con- 
tart  with  the  lower  edge  of  the  pectinalis. 


MUSCLES. 


415 


2.  The  Adductor  Brevis  is  the  smallest  of  the 
three ; it  is  situated  beneath  the  adductor  longus  and 
pectinalis,  and  on  the  outside  of  the  gracilis.  It 
arises  by  a rounded  tendon  from  the  middle  front  part 
of  the  pubes  between  its  symphysis  and  the  foramen 
thyroideunij  just  below  the  origin  of  the  first  adductor. 

It  is  inserted  into  the  upper  third  of  the  inner  edge 
of  the  linea  aspera,  between  the  trochanter  minor  and 
the  upper  edge  of  the  adductor  longus,  by  a flat  thin 
tendon. 

3.  The  Adductor  Magnus  is  below  the  other  two, 
and  is  by  far  the  largest.  It  arises,  fleshy,  from  the 
lower  part  of  the  body  of  the  pubes  and  from  its  de- 
scending ramus^  also  from  the  ascending  ramus  of  the 
ischium  as  far  as  its  tuberosity,  occupying  the  whole 
bony  surface  between  the  foramen  thyroideum  below, 
and  the  margin  of  the  pelvis. 

It  is  inserted,  fleshy,  the  whole  length  of  the  linea. 
aspera,  and  on  its  internal  margin  a tendon  is  gradually 
generated,  which  passes  downwards  to  be  inserted  into 
the  upper  part  of  the  internal  condyle  of  the  os  femo- 
ris,  and  by  a thin  edge  or  expansion  into  the  line 
leading  from  the  linea  aspera  to  the  internal  condyle. 

The  adductor  magnus  separates  the  muscles  on  the 
anterior  from  such  as  are  on  the  posterior  part  of  the 
thigh,  and  its  insertion  is  closely  connected  with  the 
origin  of  the  vastus  internus,  the  two  surfaces  adhering 
by  a short  and  compact  cellular  membrane. 


41G 


OF  THE  LOWER  EXTREMITIES. 


The  three  adductors  contribute  to  the  same  end, 
that  of  drawing  the  thigh  inwards. 

The  subject  should  now  be  turned  over  in  order  to 
enable  us  to  study  the  muscles  on  the  back  of  the 
limb. 

The  Gluteus  Magnus  arises  fleshy,  from  the  pos- 
terior third  of  the  spine  of  the  ilium,  from  the  side  of 
the  sacrum  below  it,  from  the  side  of  the  os  coccygis, 
and  from  the  posterior  surface  of  the  large  sacro- 
sciatic  ligament.  The  fibres  of  this  muscle  are  collect- 
ed into  large  fasciculi  with  deep  interstices  between 
them,  and  the  lower  edge  of  it  is  folded  over  the 
posterior  sacro-sciatic  ligament. 

Its  fibres  pass  obliquely  forwards  and  downwards, 
and  terminate  in  a thick  broad  tendon,  the  upper  part 
of  which  goes  on  the  outside  of  the  trochanter  major, 
and  is  very  strongly  inserted  into  the  fascia  femoris, 
and  the  lower  part  is  inserted  into  the  upper  third  of 
the  linea  aspera,  going  down  as  far  as  the  origin  of  the 
short  head  of  the  biceps  flexor  cruris. 

This  muscle  is  placed  immediately  under  the  skin, 
the  fasciculi  being  separated  to  some  depth  by  pro- 
cesses from  the  fascia  femoris.  It  covers  nearly  all 
the  other  muscles  on  the  back  part  of  the  pelvis,  laps 
over  its  inferior  margin  laterally,  and  conceals  the 
origins  of  the  hamstring  muscles.  It  draws  the  thigh 
backwards. 


MUSCLES. 


417 


The  Gluteus  Medius  arises  from  the  whole  length 
of  the  spine  of  the  ilium,  except  its  posterior  part,  and 
from  that  part  of  the  dorsum  of  the  bone  which  is  be' 
tween  its  spine  and  a semicircular  ridge  extending  * 
from  the  anterior  superior  spinous  process  to  the  sciatic 
notch ; also  from  the  lunated  edge  of  the  os  ilium  be- 
tween the  anterior  superior  and  anterior  inferior  spi- 
nous process,  and  from  that  part  of  the  inner  face  of 
the  fascia  femoris  which  covere  it. 

The  anterior  superior  part  of  this  muscle  is  not  co- 
vered by  the  gluteus  magnus,  but  lies  before  it.  Its 
fibres  converge,  and  are  inserted,  by  a broad  thick 
tendon,  into  the  upper  surface  of  the  trochanter  ma- 
jor, and  into  the  upper  anterior  part  of  the  shaft  of  the 
bone  just  in  front  of  the  same  trochanter. 

It  draws  the  thigh  backwards  and  outwards. 

The  Gluteus  Minimus  arises  from  that  part  of  the 
dorsum  of  the  ilium  between  the  semicircular  ridge, 
just  spoken  of,  and  the  margin  of  the  capsular  ligament 
of  the  hip  joint.  It  is  entirely  concealed  by  the 
gluteus  medius. 

Its  fibres  converge  and  terminate  in  a round  tendon, 
which  is  inserted  into  the  anterior  and  superior  part  of 
the  trochanter  major,  just  within  the  anterior  insertion 
of  the  gluteus  medius. 

It  abducts  the  thigh,  and  can  also  rotate  the  limb 
inwards. 

3 G 


418 


OF  THE  LOWER  EXTREMITIES. 


There  are  several  small  muscles  about  the  hip  joints 
the  most  of  which  can  be  seen  by  the  removal  of  the 
gluteus  magnus. 

The  Pyriformis  arises,  fleshy  and  tendinous,  with- 
in the  pelvis,  from  the  anterior  face  of  the  second, 
third,  and  fourth  bones  of  the  sacrum.  It  forms  a 
conical  belly  which  passes  out  of  the  pelvis  at  the  up- 
per part  of  the  sacro-sciatic  foramen,  receiving  a slip 
of  fibres  from  the  posterior  inferior  spinous  process  of 
the  ilium. 

It  is  inserted,  by  a round  tendon,  into  the  upper 
middle  part  of  the  trochanter  major  within  the  inser- 
tion of  the  gluteus  medius. 

It  rotates  the  limb  outwards. 

The  Gemini  are  two  small  muscles  closely  connected 
with  each  other,  which  are  situated  lower  down  on  the 
limb  than  the  pyriformis.  The  upper  one  arises  from 
the  posterior  part  of  the  root  of  the  spinous  process 
of  the  ischium ; the  lower  from  the  upper  back  part 
of  the  tuberosity  of  the  ischium. 

Being  parallel  to  each  otlier,  and  connected  by  their 
contiguous  edges,  they  are  inserted  together  into  the 
posterior  part  of  the  thigh  bone  at  the  root  of  the 
trochanter  major,  where  the  rough  pit  is. 

They  also  rotate  the  limb  outwards. 

The  Obturator  Internus  muscle  is  principally 


MUSCLES. 


419 


Situated  within  the  cavity  of  the  pelvis.  It  arises^ 
fleshy,  from  all  the  pelvic  margin  of  the  foramen  thy- 
roideum,  except  where  the  obturator  vessels  go  out, 
and  from  the  internal  face  of  the  ligamentous  mem- 
brane stretched  across  it;  also  from  the  upper  part  of 
the  plane  of  the  ischium  and  just  below  the  linea  in- 
nominata;  its  fibres  converge,  and,  forming  a tendon, 
pass  out  of  the  pelvis  over  the  trochlea  of  the  ischium 
between  the  sacro-sciatic  ligaments. 

The  tendon  is  placed  between  the  gemini  muscles, 
which  form  a sheath  for  it;  and  it  is  inserted  into  the 
pit  on  the  back  of  the  os  femoris  at  the  root  df  the 
trochanter  major. 

It  rotates  the  limb  outwards. 

The  Quadratus  Femoris  is  below  the  other  mus- 
cles. It  arises,  tendinous  and  fleshy,  from  the  ridge 
on  the  outer  side  of  the  ischium  which  constitutes  the 
exterior  boundary  of  the  tuberosity. 

Its  fibres  are  transverse,  and  are  inserted,  fleshy, 
into  the  rough  ridge  of  the  os  femoris  on  its  back  part 
which  goes  from  one  trochanter  to  the  other. 

It  rotates  the  limb  outw’ards. 

The  Obturator  Externus  is  concealed,  in  front, 
by  the  pectineus  and  triceps  adductor,  and  behind  by 
the  quadratus  femoris ; to  get  a satisfactory  view  of  it, 
therefore,  these  muscles  should  be  detached  from  the 
bone.  It  arises  from  the  whole  exterior  circurafer" 


420 


OF  THE  LOWER  EXTREMITIES. 


ence  of  the  foramen  thyroideum,  excepting  the  place 
where  the  obturator  vessels  come  out,  and  from  the 
exterior  face  of  the  ligamentous  membrane  stretched 
across  it. 

The  fibres  of  this  muscle  converge,  pass  beneath  the 
capsular  ligament  of  the  hip  joint  adhering  to  it,  and 
terminate  successively  in  a round  tendon  which  is  in- 
serted into  the  inferior  part  of  the  cavity  on  the  pos- 
terior surface  of  the  os  femoris,  at  the  root  of  the 
trochanter  major.  The  course  of  the  tendon  of  this 
muscle  is  marked  on  the  neck  of  the  thigh  bone  by  a 
superficial  fossa. 

It  rotates  the  thigh  outwards. 

The  Biceps  Flexor  Cruris  constitutes  the  outer 
hamstring,  and  is  situated  on  the  posterior  outer  part 
of  the  thigh ; it  arises  by  two  heads.  The  fii’st,  called 
the  long  head,  has  an  origin,  in  common  with  the  se- 
mitendinosus,  from  the  upper  back  part  of  the  tube- 
rosity of  the  ischium  by  a short  tendinous  head,  which, 
in  its  descent,  is  changed  into  a thick  fleshy  belly. 
The  other,  called  the  short  head,  arises,  by  an  acute 
fleshy  beginning,  from  the  linea  aspera  just  below  the 
insertion  of  the  gluteus  magnus,  and  is  continued  along 
the  lower  part  of  the  linea  aspera  from  the  ridge  lead- 
ing to  the  external  condyle. 

A thick  tendon  is  gradually  formed  on  the  outside  of 
the  muscle  and  is  inserted  into  the  upper  part  of  the 
head  of  the  fibula. 


MUSCLES. 


421 


This  muscle  flexes  the  leg  on  the  thigh.* 

The  Semitendinosus  is  on  the  inside  of  the  thigh, 
between  the  biceps  and  gracilis ; it  is  superficial,  be- 
ing immediately  under  the  fascia,  and  arises,  in  com- 
mon with  the  biceps,  from  the  back  part  of  the  tubero- 
sity of  the  ischium ; it  also  adheres,  for  three  or  four 
inches,  to  the  inner  edge  of  the  tendon  of  the  long 
head  of  the  biceps. 

About  four  inches  above  the  knee  it  terminates  in 
a long  round  tendon,  which  passes  behind  the  internal 
condyle  and  the  head  of  the  tibia,  and  is  reflected  for- 
wards to  be  inserted  into  the  side  of  the  tibia,  just  be- 
low its  tubercle  and  very  near  it,  being  lower  down 
than  the  insertion  of  the  tendon  of  the  gracilis. 

It  flexes  the  leg  on  the  thigh. 

The  Semimembkanosus  is  at  the  inner  side  of  the 
thigh;  its  upper  part  is  concealed  by  the  semitendi- 
nosus  and  the  origin  of  the  long  head  of  the  biceps, 
and  below,  it  projects  between  these  two  muscles.  It 
is  in  contact  with  the  posterior  surface  of  the  triceps 
magnus. 

It  arises,  by  a thick  round  tendon,  from  the  exterior 
upper  part  of  the  tuberosity  of  the  ischium,  which 
tendon  soon  becomes  flattened  and  sends  off  the  mus- 
cular fibres  obliquely  from  its  exterior  edge,  to  a cor- 
responding tendon  below.  The  latter  passing  behind 
the  internal  condyle  and  the  head  of  the  tibia,  de- 


422 


OF  THE  LOWER  EXTREMITIES. 


taches  a thift  aponeurotic  membrane  under  the  inner 
head  of  the  gastrocnemius,  to  cover  the  posterior  part 
of  the  capsule  of  the  joint,  and  to  be  fastened  to  the 
externa]  condyle. 

It  is  inserted,  by  a round  tendon,  into  the  inner  and 
back  part  of  the  head  of  the  tibia  just  below  the  joint. 
The  unfavourable  insertion  of  this  muscle  is  compen- 
sated by  the  course  of  its  fibres,  which  gives  it  gi’eat 
increase  of  strength. 

It  flexes  the  leg  on  the  thigh. 

Muscles  of  the  Leg. 

These  muscles  are  situated  anteriorly,  posteriorly, 
and  externally. 

The  Tibialis  Axticus  muscle  is  situated  superfi- 
cially under  the  fascia  of  the  leg,  at  the  outside  of  the 
spine  of  the  tibia,  and  in  front  of  the  interosseous  liga- 
ment. It  arises,  fleshy,  from  the  head,  outer  surface, 
and  spine  of  the  tibia,  and  from  the  interosseous  liga- 
ment, to  within  three  or  four  inches  of  the  ancle.  It 
also  arises  by  its  front  surface  from  the  internal  face  of 
the  fascia  of  the  leg. 

A rounded  long  tendon  is  formed  below,  which, 
passing  through  a distinct  noose  of  the  annular  liga- 
ment in  front  of  the  malleolus  internus,  crosses  the 
astragalus  and  os  naviculare,  and  is  inserted  into  the 
anterior  part  of  the  base  of  the  cuneiforme  internum, 


MUSCLES. 


423 


and  into  the  adjacent  part  of  the  metatarsal  bone  of  the 
great  toe. 

It  bends  the  foot,  and  presents  the  sole  obliquely 
inwards. 

The  Extensor  Longus  Digitorum  Pedis,  is  also 
superficially. placed  just  under  the  fascia  of  the  leg 
and  in  front  of  the  fibula,  being  in  contact  above  with 
the  tibialis  anticus,  and  below  with  the  extensor  pro- 
prius  pollicis.  It  arises,  tendinous  and  fleshy,  from 
the  outer  part  of  the  head  of  the  tibia,  from  the  head 
of  the  fibula,  and  almost  the  whole  length  of  its  anterior 
spine;  also  from  the  upper  part  of  the  interosseous 
ligament  and  the  internal  face  of  the  fascia  of  the 
leg. 

About  the  middle  of  the  leg  this  muscle  splits  into 
four  tendons,  which  are  confined  by  the  annular  liga- 
ment of  the  ancle,  and  then  diverging,  are  inserted 
into  the  base  of  each  small  toe,  and  expanded  over  its 
back  part  as  far  as  the  last  phalanx. 

It  extends  all  the  joints  of  the  small  toes  and  flexes 
the  foot. 

The  Peroneus  Tertius  is  rather  an  appendage  of 
the  extensor  longus,  is  found  at  its  lower  outer  part, 
and  cannot  be  naturally  separated  from  it.  It  arises 
from  the  anterior  angle  of  the  fibula,  between  its  mid- 
dle and  lower  end. 

It  is  inserted,  by  a flattened  tendon,  into  the  base 


424 


OF  THE  LOWER  EXTREMITIES. 


of  the  metatarsal  bone  of  the  little  toe,  and  assists  in 
bending  the  foot. 

The  Extensor  Proprius  Pollicis  Pedis  is  be- 
tween the  lower  part  of  the  tibialis  anticus,  and  the 
extensor  longus.  It  arises  from  the  fibula  between 
its  anterior  and  internal  angles,  by  a tendinous  and 
fleshy  origin,  which  commences  about  four  inches  be- 
low the  head  of  the  fibula,  and  continues  almost  to 
its  inferior  extremity.  A few  fibres  also  come  from 
the  interosseous  ligament,  and  from  the  lower  part  of 
the  tibia. 

The  muscle  being  half  penniforra,  the  fibres  run 
at  its  fore  part  obliquely  to  a tendon,  which  passes  un- 
der the  annular  ligament,  and  over  the  astragalus  and 
scaphoides  and  upper  internal  parts  of  the  foot,  to  be 
inserted  into  the  base  of  the  first  and  second  phalanges 
of  the  great  toe. 

On  the  outside  of  the  leg,  between  the  fibula  and 
fascia,  are  the  two  Peronei  muscles. 

The  Peroneus  Longus  arises,  tendinous  and  fleshy, 
from  the  fore  and  outside  of  the  head  of  the  fibula, 
from  the  space  on  its  outer  side  above,  between  the 
external  and  anterior  angles,  also  from  its  external 
angle  to  within  a short  distance  of  the  ancle. 

A flattened  thick  tendon  constitutes  the  outer  face 
of  the  muscle,  to  which  the  fibres  pass  obliquely.  This 


MUSCLES. 


425 


tendon  is  lodged  in  the  groove  at  the  posterior  part  of 
the  malleolus  externus,  being  confined  to  it  by  a thick 
ligamentous  noose,  and  traverses  the  outer  side  of  the 
os  calcis,  where  its  passage  is  marked  by  a superficial 
sulcus.  It  then  runs  through  the  groove  of  the  os 
cuboides,  and  lying  deep  in  the  sole  of  the  foot  next 
to  the  tarsal  bones,  is  inserted  into  the  base  of  the  in- 
ternal cuneiform  bone,  and  into  the  adjacent  part  of 
the  metatarsal  bone  of  the  gi’eat  toe. 

It  extends  the  foot  and  inclines  the  sole  obliquely 
outwards. 

The  Peroneus  Brevis  is  concealed  in  a great  de- 
gree by  the  peroneus  longus,  being  situated  between 
the  latter  and  the  extensor  longus  digitorum.  It  arises, 
tendinous  and  fleshy,  from  the  outer  surface  of  the 
fibula,  commencing  about  one  third  of  the  length  of 
the  bone  from  its  head,  and  continuing  almost  to  the 
ancle. 

A tendinous  facing  exists  externally  also  in  this 
muscle,  to  which  its  fibres  proceed  obliquely.  This 
tendon  is  continued  through  the  fossa  at  the  back  part 
of  the  malleolus  externus,  being  covered  by  the  tendon 
of  the  peroneus  longus,  and  confined  by  the  same  liga- 
mentous noose,  and  passing  through  the  superficial 
fossa  at  the  outer  side  of  the  os  calcis,  is  inserted  into 
the  external  part  of  the  base  of  the  metatarsal  bone  of 
the  little  toe.  It  extends  the  foot  and  presents  the  sole 
obliquely  downwards, 

3 H 


426 


OF  THE  LOWER  EXTREMITIES. 


The  Triceps  Siirse  is  placed  on  the  back  of  the  leg, 
and  consists  of  Gastrocnemius  and  Soleus  which  in  fact 
form  but  one  muscle. 

The  Gastrocnemius  is  the  most  superficial  and 
conceals  the  other  in  consequence  of  its  breadth.  It 
arises  from  the  condyles  of  the  femur  by  two  heads. 
One  head  arises,  tendinous,  from  the  upper  back  part 
of  the  internal  condyle,  and  fleshy,  from  the  ridge  lead- 
ing to  the  linea  aspera;  the",  other  head  arises,  by  a 
broad  tendon  in  the  same  way,  from  the  external  con- 
dyle and  the  line  above  it.  A triangular  vacancy  is 
left  between  the  heads  of  the  muscle  for  tlie  passage  of 
the  popliteal  vessels;  they  then  join  together,  but  in 
such  a way  that  the  appearance  of  two  bellies  is  dis- 
tinctly preserved,  of  which  the  internal  is  the  largest. 
The  muscular  fibres  pass  from  a broad  tendinous  facing 
on  the  back  to  a corresponding  one  on  the  front  sur- 
face of  the  muscle,  from  the  latter  of  which  comes  the 
Tendo  Achillis. 

The  heads  of  the  gastrocnemius  being  detached 
from  their  origin,  we  then  see  the  Soleus  or  Gastroc- 
nemius Interniis. 

The  Soleus  arises,  fleshy,  from  the  posterior  part 
of  the  head  of  the  fibula  and  from  the  external  angle 
of  that  bone  for  two-thirds  of  its  length  down,  behind 
the  peroneus  longus.  It  also  arises,  fleshy,  from  the 
oblique  ridge  on  the  posterior  surface  of  the  tibia. 


MUSCLES. 


427 


just  at  the  lower  edge  of  the  popliteus  muscle,  and 
from  the  internal  angle  of  the  tibia  for  four  or  five 
inches.  The  two  heads  are  separated  for  the  passage 
of  the  posterior  tibial  vessels. 

The  body  of  this  muscle  has  a great  intermixture 
of  tendinous  matter  in  it,  and  from  its  lower  extremity 
proceeds  the  other  origin  of  the  tendo  achillis;  about 
three  or  four  inches  above  the  heel,  this  tendon  joins 
the  anterior  face  of  the  tendon  of  the  gastrocnemius, 
and  by  the  union  ofithe  two  is  formed  the  Tendo 
Achillis,  which  is  inserted  into  the  posterior  inferior 
surface  of  the  os  calcis  at  its  tubercles. 

These  two  muscles  extend  the  foot,  and  are  all-im- 
portant in  walking. 

The  Plantaris  is  a singular  little  muscle  conceal- 
ed by  the  gastrocnemius,  and  has  a short  fleshy  belly 
and  a long  tendon.  It  arises,  fleshy,  from  the  ridge 
of  the  os  femoris  just  above  the  external  condyle;  pas- 
ses across  the  capsular  ligament  of  the  joint,  adhering 
to  it  in  its  course;  the  belly  terminates  somewhat  be- 
low the  head  of  the  tibia  in  a long  delicate  tendon 
which  descends  between  the  inner  head  of  the  soleus 
and  the  gastrocnemius. 

At  the  place  where  these  tendons  unite,  the  tendon 
of  the  plantaris  emerges  from  between  them,  and,  run- 
ning at  the  inner  edge  of  the  tendo  achillis,  is  insert- 
ed into  the  inside  of  the  os  calcis  just  before  the  in- 
sertion of  the  tendo  achillis. 

It  extends  the  foot. 


428 


OF  THE  LOWER  EXTREMITIES. 


The  PoPLiTEUs  is  a triangular  muscle  on  the  back 
of  the  knee  joint.  It  arises  from  a deep  depression  on 
the  exterior  face  of  the  external  condyle,  by  a thick 
round  tendon,  which  passes  through  the  capsular  liga- 
ment, being  connected  with  the  external  semilunar  car- 
tilage, and  then  forms  a fleshy  belly  that  passes  ob- 
liquely inwards  and  downwards. 

It  is  inserted,  fleshy,  into  the  oblique  ridge  on  the 
back  of  the  tibia  just  below  its  head,  and  into  the  tri- 
angular depression  above  it. 

It  bends  the  leg,  and  when  bent,  rotates  it  inwards. 

By  removing  the  soleus  we  expose  three  other  mus- 
cles on  the  back  of  the  leg,  the  Tibialis  Posticus,  the 
Flexor  Longus  Digitorum  Pedis,  and  the  Flexor  Lon- 
gus  Pollicis  Pedis.  These  muscles  are  covered  by  a 
thick  strong  fascia,  from  which  some  of  their  fibres 
originate,  and  which  should  be  removed. 

The  Flexor  Longus  Digitorum  Pedis  Perfo- 
RANS  is  behind  the  tibia,  and  at  the  inner  edge  of  the 
tibialis  posticus.  It  arises,  by  an  acute,  tendinous,  and 
fleshy  beginning,  from  the  back  of  the  tibia  a little 
below  the  popliteus  muscle,  its  origin  being  continued 
from  the  internal  angle  of  the  tibia  almost  to  the  ancle 
joint.  It  arises  also,  by  tendinous  and  fleshy  fibres, 
from  the  outer  edge  of  the  tibia,  just  above  its  connexion 
with  the  fibula  at  the  ancle;  and  between  this  double 
order  of  fibi’es  the  tibialis  posticus  lies. 


MUSCLES. 


429 


The  fibres  pass  obliquely  into  a tendon  at  the  pos- 
terior edge  of  the  muscle,  which  runs  in  the  groove  of 
the  internal  malleolus,  and  is  confined  there  by  a strong 
ligamentous  sheath.  The  tendon  then  gets  to  the  sole 
of  the  foot  along  the  sinuosity  of  the  os  calcis,  and, 
being  joined  by  a considerable  tendon  detached  from 
the  flexor  longus  pollicis,  it  divides  into  four  branches 
which  are  appropriated  to  the  four  small  toes. 

These  tendons  are  inserted  into  the  bases  of  the  last 
phalanges  of  the  lesser  toes,  are  very  near  the  tarsal 
bones,  and,  from  perforating  the  tendons  of  the  flexor 
brevis,  correspond  with  the  flexor  perforans  of  the 
hand. 

This  muscle  flexes  the  small  toes  and  extends  the 
foot. 

The  Flexor  Longus  Pollicis  Pedis  is  a stout 
muscle  formed  of  oblique  fibres,  situated  on  the  back 
part  of  the  fibula,  and  at  the  outer  side  of  the  tibialis 
posticus.  It  arises  by  an  acute,  tendinous,  and  fleshy 
beginning  from  the  posterior  flat  surface  of  the  fibula, 
commencing  about  three  inches  from  its  head,  and 
continuing  almost  to  the  ancle. 

The  tendon  of  this  muscle  is  large  and  round;  i£ 
forms  gradually,  and  constitutes  a facing  to  the  poste^ 
rior  edge  of  the  muscle.  It  passes  through  a superfi- 
cial fossa  of  the  tibia  at  the  back  of  the  ancle,  near  its 
middle,  and  from  thence  through  a notch  in  the  back 
edgc^  of  the  astragalus  to  the  sole  of  the  foot,  where  it 


430 


OF  THE  LOWER  EXTREMITIES. 


crosses  the  tendon  of  the  flexor  longus  digitorunij 
giving  off  the  branch  just  mentioned  to  join  it.  This 
tendon  is  deeper  seated  in  the  foot  than  the  other. 

The  tendon  of  the  flexor  longus  pollicis  is  inserted 
into  the  last  joint  of  the  great  toe.  It  bends  the  great 
toe,  and  from  its  connexion  with  the  others  will  bend 
them  also. 

The  Tibialis  Posticus  is  placed  between,  and 
concealed  by  the  two  last  muscles.  It  arises,  by  a nar- 
row fleshy  beginning,  from  the  fi-ont  of  the  tibia,  at 
the  under  surface  of  the  process  which  joins  it  to  the 
fibula,  and  then  gets  to  the  back  of  the  leg,  through  a 
hole  in  the  interosseous  ligament.  It  eontinues  its 
origin  from  the  whole  of  the  interosseous  ligament, 
and  from  the  surfaces  of  the  tibia  and  fibula,  bordering 
on  the  ligament,  excepting  one-third  of  the  lower  part 
of  the  fibula,  and  rather  more  of  the  lower  part  of  the 
tibia. 

The  fleshy  fibres  run  obliquely  to  a middle  tendon, 
which  passes  in  the  groove  at  the  back  of  the  malleo- 
lus internus,  and  is  inserted  into  the  upper  internal 
part  of  the  os  naviculare.  This  tendon  also  divides 
in  such  a way  as  to  be  inserted  into  the  internal  and 
external  cuneiform  bones,  into  the  os  cuboides,  and  os 
calcis. 

It  extends  the  foot,  and  presents  the  sole  obliquely 
inwards. 


MUSCLES. 


431 


Of  the  Muscles  of  the  Foot. 

The  Ext&nsor  Brevis  Digitorum  Pedis  is  the 
only  muscle  on  the  superior  surface  of  the  foot,  It  is 
placed  beneath  the  tendons  of  the  extensor  longus,  and 
arises,  tendinous  and  fleshy,  from  the  fore  upper  part 
of  the  os  calcis.  It  forms  a short  fleshy  belly,  which 
is  partially  divided  into  four  parts ; from  these  bellies 
proceed  as  many  tendons,  which  crossing  very  oblique- 
ly the  tendons  of  the  extensor  longus,  are  inserted  into 
the  great  toe  and  the  three  next  toes,  by  joining  with 
the  tendons  of  the  extensor  longus,  which  are  spread 
over  their  backs.  It  extends  the  toes. 

The  Sole  of  the  Foot  is  protected,  in  the  first  place, 
by  an  unusual  thickness  of  its  euticle,  which  is  increas- 
ed in  such  parts  as  are  most  pressed  upon,  as  the  heel, 
and  the  ball  of  the  great  toe. 

Beneath  it,  is  a thick  layer  of  adipose  matter,  found, 
in  the  most  emaciated  as  well  as  the  most  corpulent 
subjects,  which  seems  to  be  less  under  the  influence 
of  the  eauses  producing  a diminution  or  increase  of 
fat,  than  the  adipose  matter  in  any  other  part  of  the 
body.  It  is  collected  into  granulations  separated  from 
each  other  by  processes  of  condensed  cellular  mem- 
brane resembling  ligament,  that  pass  from  the  inte- 
rior surface  of  the  skin  to  the  aponeurosis  plantaris. 
It  fills  up  completely  all  the  fissures  in  this  aponeu- 


432 


OF  THE  LOWER  EXTREMITIES. 


rosis,  and  adheres  very  closely  to  it,  so  that  it  requires 
much  trouble  to  get  out  a fair  dissection  of  the  apo- 
neurosis. 

The  Aponeurosis,  or  Fascia  Plaxtaris,  is  a 
ligamentous  membrane,  extending  from  the  tubercles  of 
the  os  calcis,  to  the  anterior  ends  of  the  metatarsal 
bones.  It  is  triangular,  and  corresponds  with  the  out- 
line of  the  foot,  by  being  narrow^  behind,  and  broad 
before.  It  is  divided  into  three  parts,  according  to  the 
division  of  the  muscles  of  the  foot,  one  part  lying  on 
the  muscles  at  the  outside  of  the  sole,  another  on  the 
muscles  at  the  inside  of  the  sole,  and  the  third  being 
between  the  other  two.  The  internal  and  external 
portions  are  thin,  and  reticulated ; they  extend  from 
the  tubercles  of  the  os  calcis  to  the  roots  of  the  inter- 
nal and  external  metatarsal  bones,  and  are  scarcely 
seen  beyond  them.  But  the  central  portion  is  remark- 
ably strong  near  the  heel,  and  diminishes  in  thickness 
as  it  spreads  out.  Anteriarly,  it  is  divided  into  five 
portions,  one  for  each  metatarsal  bone;  each  of  these 
portions  is  bifurcated,  and  dips  down  to  be  inserted  on 
either  side  of  the  metatarsal  bone  near  its  head.  Be- 
tween the  prongs  of  each  bifurcation  pass  the  tendons, 
nerves,  &c.  to  the  toes.  The  interior  face  of  this 
membrane  affords  origin  to  many  of  the  muscular  fibres, 
and  from  it  proceed  vertical  partitions,  separating  the 
muscles  of  the  middle  of  the  foot  from  such  as  are  on 
each  side  of  it. 


MUSCLES. 


433 


When  the  Aponeurosis  Plantaris  is  removed,  we  see 
three  muscles ; the  middle  one  under  the  large  central 
portion  of  the  aponeurosis,  is  the  Flexor  Brevis  Digi- 
torum  Pedis,  the  outer  is  the  Abductor  Minimi  Digiti, 
and  the  inner  the  Abductor  Pollicis  Pedis. 

The  Flexor  Brevis  Digitorum  Pedis  arises, 
fleshy,  from  the  tubercle  of  the  os  calcis  by  a narrow 
beginning,  also  from  the  interior  surface  of  the  apo- 
neurosis, and  the  tendinous  septa  between  it  and  the 
contiguous  muscles. 

It  forms  a fleshy  belly  going  nearly  as  far  forwards 
as  the  middle  of  the  metatarsal  bones ; there  it  divides 
into  four  tendons,  which  go  to  the  smaller  toes.  These 
are  perforated  by  the  tendons  of  the  flexor  longus,  and 
are  inserted  into  the  sides  of  the  second  phalanges. 
The  tendon  for  the  little  toe  is  often  deficient. 

It  bends  the  second  joint  of  the  toes. 

By  detaching  this  muscle  from  its  origin  and  turn- 
ing it  down,  we  bring  into  view  the  tendon  of  the 
Flexor  Longus  Digitorum  Pedis,  and  its  attachments 
behind,  to  the  tendinous  slip  from  the  Flexor  Longus 
Pollicis,  and  to  the  Massa  Carnea  Jacobi  Sylvii,  or 
Flexor  Accessorius,  and  before,  to  the  Lumbricales 
muscles. 

The  Flexor  Accessorius  is  at  the  outside  of  the 
tendon  of  the  flexor  longus.  It  arises,  fleshy,  from 

3 I 


434 


OF  THE  LOWER  EXTREMITIES. 


the  inside  of  the  sinuosity  of  the  os  calcis,  and,  by  a 
thin  tendon,  from  the  outside  of  the  bone  before  its 
tubercle. 

It  is  inserted,  fleshy,  into  the  outside  of  the  tendon 
of  the  flexor  longus,  just  at  its  division  into  four  ten- 
dons. Like  a second  hand  at  a rope,  it  assists  in  flex- 
ing the  toes. 

The  Lumbricales  Pedis  are  four  small  tapering 
muscles  which  arise  from  the  tendon  of  the  flexor  lon- 
gus just  after  its  division,  or  while  it  is  in  the  act  of 
dividing.  One  of  them  is  appropriated  to  each  lesser 
toe,  and  is  inserted  into  the  inside  of  its  first  phalanx, 
and  into  the  tendinous  expansion  that  is  sent  off  from 
the  extensor  muscle  to  cover  its  dorsum. 

They  increase  the  flexion  of  the  toes  and  draw  them 
inwards. 

The  Abductor  Pollicis  Pedis  arises,  tendinous 
and  fleshy,  from  the  internal  anterior  part  of  the  tu- 
berosity of  the  os  calcis,  from  a ligament  extended 
from  the  tuberosity  to  the  sheath  of  the  tendon  of  the 
tibialis  posticus,  from  the  internal  side  of  the  navicu- 
lare,  and  from  the  cuneiforme  internum. 

It  forms  the  internal  margin  of  the  sole  of  the  foot, 
and  is  inserted,  tendinous,  into  the  internal  sesamoid 
bone  and  into  the  base  of  the  first  phalanx  of  the  great 
toe. 

It  draws  the  great  toe  from  the  rest. 


MUSCLES.  435 

The  Flexor  Brevis  Pollicis  Pedis  is  situated  im- 
mediately at  the  exterior  edge  of  the  abductor  pollicis. 
It  consists  of  two  bellies,  parallel  with  each  other,  but 
separated  by  the  tendon  of  the  flexor  longus  pollicis; 
one  is  inseparably  connected  with  the  tendon  of  the 
abductor  pollicis,  and  the  other  with  the  adductor 
pollicis. 

It  arises,  tendinous,  from  the  under  part  of  the  os 
calcis,  just  behind  its  connexion  with  the  os  cuboides, 
and  from  the  under  part  of  the  external  cuneiform 
bone. 

The  internal  belly  is  inserted,  tendinous,  into  the 
internal  sesamoid  bone  along  with  the  tendon  of  the 
abductor  pollicis;  and  the  external  belly  is  inserted, 
tendinous,  into  the  external  sesamoid  bone  along  with 
the  ■ tendon  of  the  adductor  pollicis.  Each  insertion 
is  continued  on  to  the  base  of  the  first  phalanx  of  the 
great  toe. 

It  flexes  the  great  toe. 

The  Adductor  Pollicis  Pedis  is  situated  at  the 
outside  of  the  flexor  brevis,  and  iS  extended  obliquely 
across  the  metatarsal  bones.  It  arises,  tendinous,  at 
the  external  part  of  the  foot,  from  a strong  ligament 
which  is  stretched  from  the  os  calcis  to  the  os  cuboides, 
and  from  the  roots  of  the  second,  third,  and  fourth 
metatarsal  bones.  ‘ 

It  is  inserted,  tendinous,  into  the  external  sesamoid 
bone,  which  insertion  is  continued  to  the  first  phalanx 


436 


OF  THE  LOWER  EXTREMITIES. 


of  the  great  toe,  and  is  closely  united  to  the  tendon  of 
the  external  head  of  the  flexor  brevis  pollicis. 

It  draws  the  great  toe  towards  the  others. 

The  Abductor  Minimi  Digiti  Pedis  forms  the 
external  margin  of  the  sole  of  the  foot,  and  is  imme- 
diately beneath  the  aponeurosis  plantaris.  It  arises, 
tendinous  and  fleshy,  from  the  outer  side  of  the  tuber 
of  the  os  calcis,  and  also  from  the  exterior  part  of  the 
base  of  the  metatarsal  bone  of  tbe  little  toe. 

It  is  inserted,  by  a round  tendon,  into  the  exterior 
part  of  the  base  of  the  first  phalanx  of  the  little  toe. 

It  draws  the  little  toe  from  the  other  toes. 

The  Flexor  Brevis  Minimi  Digiti  Pedis  is  just 
within  the  tendon  of  the  abductor  minimi  digiti.  It 
arises  from  the  ligament  which  is  extended  from  the 
tuberosity  of  the  cuboid  bone  to  the  heads  of  all  the 
metatarsal  bones;  also  from  the  root  of  the  fifth  meta- 
tarsal bone. 

It  is  inserted,  by  a tendon,  into  the  lower  part  of 
the  first  phalanx  of  -the  little  toe  at  its  base,  and  into 
the  head  of  the  metatarsal  bone  of  the  same  toe.  It 
bends  the  little  toe. 

The  Transversalis  Pedis  is  placed  beneath  the 
tendons  of  the  flexor  muscles.  It  is  small,  and  lies 
across  the  anterior  extremities  of  the  metatarsal  bones. 
It  arises,  tendinous,  from  the  capsular  ligament  of  the 


MUSCLES. 


437 


first  joint  of  the  little  toe;  it  also  arises  from  the  cap- 
sule of  the  first  joint  of  the  next  toe. 

It  is  inserted  into  the  exterior  face  of  the  common 
tendon  of  the  adductor  and  flexor  brevis  pollicis  at  the 
external  sesamoid  bone. 

It  approximates  the  heads  of  the  metatarsal  bones. 

The  Interosseous  Muscles  are  seven  in  number,  four 
of  which  may  be  seen  on  the  upper  surface  of  the  foot. 
There  are  two  to  the  first  small  toe,  two  to  the  second, 
two  to  the  third,  and  one  to  the  fourth  or  little  toe. 
The  muscles  seen  on  the  upper  side  of  the  foot  are  for 
the  most  part  double  headed,  that  is,  they  arise  from 
the  contiguous  surfaces  of  the  metatarsal  bones. 

The  Interosseus  Primus  Digiti  Primi  Pedis,  or 
the  Abductor  Indicis  Pedis,  is  seen  superiorly.  It 
is  placed  between  the  metatarsal  bone  of  the  great  toe 
and  the  first  small  toe,  and  arises,  fleshy,  by  a double 
head,  from  the  opposed  surfaces  of  their  roots. 

It  is  inserted,  tendinous,  into  the  inside  of  the  root 
of  the  first  joint  of  the  first  small  toe,  and  pulls  it  in- 
wards. 

The  Interosseus  Secundus  Primi  Digiti,  or  the 
Adductor  Indicis  Pedis,  is  also  external  or  above. 
It  is  situated  between  the  metatarsal  bones  of  the  first 
and  second  small  toes,  arises  from  the  opposed  surfaces 
of  their  roots  by  a double  fleshy  and  tendinous  head. 


438 


OF  THE  LOWER  EXTREMITIES. 


It  is  inserted  into  the  outside  of  the  first  phalanx  of 
the  same  toe  by  a tendon.  It  draws  this  toe  outwards. 

The  Interosseus  Primus  Secundi  Digiti  Pedis, 
or  the  Abductor  Medii  Digiti,  is  at  the  bottom  of 
the  foot,  and  arises  from  the  inside  of  the  metatarsal 
bone  of  the  second  small  toe. 

It  is  inserted  into  the  inside  of  the  first  phalanx  of 
the  second  toe. 

It  draws  this  toe  inwards. 

The  Interosseus  Secundus  Digiti  Secundi,  or 
the  Adductor  Medii  Digiti,  is  seen  at  the  upper 
part  of  the  foot,  between  the  second  and  third  meta- 
tarsal bones  of  the  lesser  toes,  arising  from  the  oppo- 
sed surfaces  of  their  roots. 

It  is  inserted,  tendinous,  into  the  outside  of  the  base 
of  the  first  phalanx  of  the  second  small  toe.  It  draws 
this  toe  outwards. 

The  Interosseus  Primus  Digiti  Tertii,  or  the 
Abductor  Tertii  Digiti,  is  in  the  sole  of  the  foot. 
It  arises  from  the  inside  of  the  metatarsal  bone  of  the 
third  toe  near  its  root,  and  is 

Inserted,  tendinous,  into  the  inside  of  the  base  of 
the  first  phalanx  of  the  third  toe. 

It  draws  this  toe  inwards. 


The  Interosseus  Secundus  Digiti  Tertii  or 


MUSCLES. 


439 


the  Adductor  Tertii  Digiti,  is  seen  on  the  upper 
surface  of  the  foot,  occupying  the  interval  of  the  meta- 
tarsal bones  of  the  third  and  fourth  small  toes,  and 
arises,  by  a double  head,  from  the  opposite  surfaces  of 
their  roots. 

It  is  inserted,  tendinous,  into  the  outside  of  the  root 
of  the  first  phalanx  of  the  third  small  toe. 

It  draws  this  toe  outwards. 

The  Interosseus  Digiti  Minimi  is  on  the  under 
surface  of  the  foot.  It  arises  from  the  inside  of  the 
base  of  the  metatarsal  bone  of  the  fourth  small,  or  the 
little  toe,  and  is 

Inserted,  tendinous,  into  the  inside  of  the  first 
phalanx  of  the  little  toe.  It  draws  this  toe  inwards. 
It  is  also  called.  Abductor  Minimi  Digiti  Pedis;  but 
this  name  has  rather  a tendency  to  confuse,  as  one  of 
the  muscles,  as  stated,  on  the  outer  side  of  the  sole  of 
the  foot,  has  the  same  name. 


440 


OF  THE  LOWER  EXTREMITIES. 


Section  III. 

Of  the  Blood  Vessels  of  the  Lower  Extremities. 

The  Femoral  Artery,  (Arteria  Femoralis,)  is  a 
continuation  of  the  external  iliac.  It  appears  first  on 
the  thigh,  half-way,  or  nearly  so,  between  the  sym- 
physis pubis  and  the  anterior  superior  spinous  process 
of  the  ilium ; emerging  from  beneath  Poupart’s  liga- 
ment, it  is  there  covered  only  by  the  skin  and  fascia  of 
the  part,  having  the  femoral  vein  at  its  inside,  and  the 
trunk  of  the  anterior  crural  nerve,  about  half  an  inch 
from  it  on  the  outside.  It  lies  upon  the  psoas  magnus 
muscle,  crosses  the  pectinalis,  and  the  whole  of  the  in- 
sertion of  the  adductor  longus  muscle.  About  one- 
third  of  the  length  of  the  thigh  bone  from  below,  it 
penetrates  the  insertion  of  the  adductor  magnus  and 
gets  to  the  ham,  being  then  behind  the  leg.  For  the 
upper  third  of  its  course  the  femoral  artery  is  at  the 
inner  edge  of  the  rectus  femoris,  and  but  a little  dis- 
tance from  it ; it  then  inclines  inwards  and  occupies  the 
angle  formed  by  the  contact  of  the  vastus  internus, 
and  the  adductor  longus.  Above,  the  sartorius  is  at 
its  outside;  but  as  this  muscle  inclines  very  rapidly  in- 
wards, immediately  after  its  origin,  it  in  a little  time 
begins  to  pass  along  the  external  margin  of  the  artery, 
and  shortly  afterwards  covers  the  artery  completely  to 


BLOOD  VESSELS. 


441 


the  place  where  it  penetrates  the  adductor.  Where 
the  artery  lies  in  the  angle  formed  by  the  adductor 
longus,  and  the  vastus  internus,  it  is  covered  by  a 
strong  interlacing  of  tendinous  fibres  from  the 
muscles^  and  is  also  enveloped  by  its  own  cellular 
coat. 

To  cut  upon  the  femoral  artery  in  any  part  of  its 
course,  lay  the  subject  horizontally,  and  turn  the  leg 
outwards,  so  that  the  external  margin  of  the  sole  of  the 
foot  will  be  in  contact  or  nearly  so  with  the  table.  A 
line  drawn  then  from  midway  between  the  anterior 
superior  spine  of  the  ilium,  and  the  symphysis  pubis, 
to  the  centre  of  the  internal  condyle  of  the  os  femoris, 
will  be  precisely  over  it.* 

The  following  branches  come  from  the  Femoral 
Artery : 

1.  The  first  is  called  by  Haller,  Arteria  Ad  Cutem 
Abdominis.  From  this  a branch  is  sent  upwards  to- 
wards the  umbilicus  under  the  skin,  and  one  more  to 
supply  the  inguinal  glands. 

2.  The  External  Pumc  (Arteri®  Pudendse  Ex- 
ternse,)  two  or  three  in  number;  they  are  sent  to  the 
integuments  and  lymphatic  glands  of  the  groin,  also  to 
the  skin  of  the  penis  and  scrotum,  or  to  the  labia  ex- 
terna. One  of  these  trunks  arises  from  the  upper 

* Marjolin. 

3 K 


442 


OF  THE  LOWER  EXTREMITIES. 


internal  part  of  the  femoral  artery,  and  the  other  some- 
times from  the  profunda. 

The  arteries  as  yet  mentioned,  anastomose  freely 
with  each  other;  are  irregular  in  their  number,  size, 
and  origin,  but  for  the  most  part  do  not  exceed  the 
size  of  a common  knitting-needle. 

3.  The  Profound  Artery,  (Arteria  Profunda  Fe- 
moris,)  is  very  happily  called,  by  Professor  Chaussier, 
La  Grande  Musculaire  De  La  Cuisse,  in  consequence 
of  its  distribution.  It  is  almost  equal  in  size  to  the  femo- 
Tal  itself,  and  arises  from  its  posterior  part  on  a level 
with  the  trochanter  minor,  but  sometimes  only  five  or 
six  lines  below  PouparPs  Ligament.  It  immediately 
begins  to  give  olf  branches  externally  and  internally, 
but  the  main  trunk  of  the  artery  continues  for  several 
inches  in  contact  with  the  femoral  artery  or  nearly 
so,  and  beneath  it.  It  then  terminates  gradually  by 
branches  which  penetrate  to  the  back  of  the  thigh. 

The  profunda  femoris  is  distributed  as  follows : 

a.  The  External  Circumflex,  (Arteria  Circum- 
flexa  Externa,)  arises  from  its  external  superior  part, 
sometimes,  however,  from  the  femoral  itself;  it  passes 
outwards  under  the  sartorius  and  the  rectus  femoris, 
and  divides  into  two  secondary  branches.  The  superior 
and  shorter  of  these  is  distributed  to  the  parts  about 
the  trochanter  major,  as  the  anterior  edges  of  the 
gluteus  medius  and  minimus,  the  capsule  of  the  hip 


BLOOD  VESSELS. 


443 


joints  and  the  heads  of  the  extensor  muscles.  The 
second  goes  along  the  outside  of  the  thigh  to  the  pa- 
tella, and  is  about  the  size  of  a crow-quill.  It  first 
passes  obliquely  between  the  rectus  and  the  crureus, 
and  then  vertically  under  the  anterior  margin  of  the 
vastus  externus,  between  it  and  the  crureus  till  it  ter- 
minates about  the  knee,  by  anastomosing  with  the  arti- 
cular arteries.  It  is  principally  distributed  to  the 
erurseus  and  vastus  externus. 

b.  The  Internal  Circumflex,  (Art.  Circumflexa 
Interna,)  arises  from  the  inner  side  of  the  profunda, 
just  below  the  external  circumflex,  but  sometimes  it 
also  comes  from  the  femoral.  It  is  somewhat  under 
the  size  of  the  other,  and  penetrates  between  the  psoas 
magnus  and  pectinalis ; it  winds  under  the  neck  of  the 
os  femoris,  and  divides  into  two  branches  which  supply 
the  contiguous'  parts,  as  the  heads  of  the  muscles  and 
the  joint. 

c.  Several  ramifications  are  also  sent  from  the  pro- 
funda to  supply  the  anterior  faces  of  the  adductor 
muscles ; they  are  irregular  in  number,  size,  and  place 
of  origin,  and  have  no  appropriated  names. 

d.  The  Perforating  Arteries,  (Rami  Profundi 
Perforantes, ) three  or  four  in  number,  are  given  off 
successively,  are  numerically  named,  and  all  penetrate 


444 


OF  THE  LOWER  EXTREMITIES. 


the  adductor  muscles  near  the  thigh  bone  to  get  to  the 
back  of  the  thigh. 

The  first  arises  immediately  below  the  little  tro- 
chanter, and,  gets  through  the  adductor  magnus  just 
below  the  quadratus  femoris,  to  be  distributed  about 
the  heads  of  the  hamstring  muscles. 

The  second  penetrates  the  adductor  magnus  at  the 
lower  part  of  the  insertion  of  the  gluteus  maximus  into 
the  linea  aspera,  to  be  distributed  about  there  and  to 
the  corresponding  section  of  the  long  head  of  the 
biceps  flexor  cruris. 

The  third  penetrates  the  adductor  magnus  a little 
below  the  commencement  of  the  origin  of  the  short 
head  of  the  biceps,  and  is  distributed  thereabout. 

The  fourth  penetrates  the  adductor  magnus  about  au 
inch  and  a half  above  the  hole  for  the  femoral  artery, 
and  is  distributed  to  the  neighbouring  part  of  the 
adductor  and  to  the  hamstring  muscles. 

After  the  origin  of  the  profunda,  the  femoral  artery 
gives  off  three  or  four  twigs  the  size  of  a large  knit- 
ting-needle, which  are  disposed  of,  upon  the  sartorius, 
adductors,  vastus  internus,  and  integuments,  but  they 
are  too  irregular  in  number,  origin,  and  course  for 
systematic  description. 

The  Anastomosing  Artery,  (Arteria  Anastomo- 
tica,)  the  last  branch  of  the  femoral,  is  sent  from  it  just 
before  it  enters  the  aperture  in  the  adductor  magnus. 
This  artery  descends,  in  the  course  of  the  tendon  of 


BLOOD  VESSELS. 


445 


this  adductor,  to  the  knee,  in  front  of  the  tendon,  be- 
tween it  and  the  vastus  internus  muscle.  It  is  distri- 
buted to  the  parts  lying  along  its  course. 

The  Popliteal  Artery,  (Arteria  Poplitsea)  is  the 
continuation  of  the  femoral  after  the  latter  has  passed 
through  the  adductor  tendon,  and  extends  from  this 
point  to  the  opening  in  the  interosseous  ligament  of 
the  leg,  just  below  the  heads  of  the  bones.  Its  first 
act  is  to  cross  obliquely  the  os  femoris  as  far  as  its 
middle ; it  then  passes  in  a vertical  line  downwards, 
very  nearly  over  the  centre  of  the  os  femoris,  knee 
joint,  and  head  of  the  tibia,  being  only  separated  from 
these  parts  in  consequence  of  a thick  envelope  of  fat, 
which  fills  up  the  hollow  of  the  ham,  and  protects  the 
artery  from  the  effects  of  sudden  flexions  of  the  part 
and  of  bruises.  The  popliteal  artery  sends  off  the 
following  branches : 

1.  The  Superior  Internal  Articular  Artery,  (Arti- 
cularis  Superior  Interna)  sometimes  exists  as  two 
trunks;  it  arises  just  above  the  internal  condyle,  per- 
forates the  adductor  tendon,  and,  going  horizontally, 
is  spent  oh  the  inner  side  of  the  joint  above. 

2.  The  Superior  External  Articulating  Artery, 
(Articularis  Superior  Externa)  arises  just  above  the 
external  condyle,  passes  horizontally  between  the 
femur  and  the  biceps  flexor,  and  is  distributed  to  the 
upper  external  parts  of  the  joint. 

3.  The  Middle  Articular,  (i\rticularis  Media) 


446 


OF  THE  LOWER  EXTREMITIES. 


sometimes  comes  from  one  of  the  others;  it  is  distri- 
buted to  the  posterior  middle  parts  of  the  knee  joint. 

4.  The  Inferior  Internal  Articular  Artery,  ( Articu- 
laris  Inferior  Interna)  arises  on  a level  with  the  infe- 
rior part  of  the  internal  condyle.  It  descends  ob- 
liquely, passes  between  the  lateral  ligament  and  the 
head  of  the  tibia,  and  then  mounts  towards  the  patella, 
to  be  distributed  in  numerous  branches. 

5.  The  Inferior  External  Articular  Artery,  (Arti- 
cularis  Inferior  Externa,)  arises  near  the  last,  and  some- 
times they  are  derived  from  a common  trunk.  It  pas- 
ses between  the  external  lateral  ligament  and  the  head 
of  the  tibia,  mounts  afterwards  towards  the  patella,  and 
is  then  minutely  ramified  on  the  lower  external  parts 
of  the  knee  joint. 

The  upper  articular  arteries  anastomose  with  the 
lower,  and  also  with  the  anastomotic  and  the  long 
branch  of  the  external  circumflex. 

Below  the  knee,  the  popliteal  artery  is  over  the  po- 
pliteus  muscle  and  between  the  heads  of  the  gastroc- 
nemius. Here  it  sends  olf  a large  branch  to  each  head 
of  the  gastrocnemius  muscle,  and  small  irregular  bran- 
ches to  the  other  muscles,  and  sometimes  the  nutritious 
artery  of  the  tibia. 

On  a level  with  the  aperture  of  the  interosseous  liga- 
ment, the  popliteal  artery  may  be  considered  as  ter- 
minating by  a division  into  two  large  branches,  tlie  An- 
terior Tibial,  and  the  Posterior  Tibial. 


BLOOD  VESSELS. 


447 


The  Anterior  Tibial  Artery,  (Arteria  Tibialis 
Anterior^)  after  getting  through  the  interosseous  fora- 
men, passes  down  the  leg  in  front  of  the  interosseous 
ligament  and  in  contact  with  it;  it  passes  also  over  the 
middle  of  the  ancle  joint  to  the  dorsum  of  the  foot, 
and  is  continued  in  a straight  line  to  the  interval  be- 
tween the  metatarsal  bone  of  the  great  toe,  and  of  the 
one  next  to  it.  This  artery  is  situated  under  a line 
drawn  from  the  middle  anterior  part  of  the  head  of 
the  fibula,  to  the  middle  of  the  ancle  joint  in  front, 
and  is  continued  in  the  course  of  a line  drawn  from 
this  latter  point  to  the  junction  of  the  two  first  me- 
tatarsal bones.  Above,  it  is  placed  between  the  tibialis 
anticus  and  the  extensor  longus  digitorum ; below,  on 
the  leg  between  the  extensor  pollicis  and  the  tibialis 
anticus;  and  while  engaged  with  the  tendons  of  the 
muscles  under  the  annular  ligament  of  the  joint,  it 
gets  to  the  fibular  side  of  the  tendon  of  the  extensor 
pollicis. 

The  anterior  tibial  artery  gives  off  several  branches, 

1,  The  Recurrent  Tibial,  (Tibialis  Recurrens) 
penetrates  the  head  of  the  tibialis  anticus  muscle,  and 
is  distributed  about  the  exterior  and  anterior  part  of 
the  head  of  the  tibia,  and  the  patella. 

2.  Several  small  arterial  twigs  are  then  sent  to  the 
muscles  and  periosteum  on  the  fore  part  of  the  leg,  but 
they  have  no  name. 


448 


OF  THE  LOWER  EXTREMITIES. 


3.  The  Internal  Malleolar,  (Malleolaris  Inter- 
na) arises  from  the  anterior  tibial  somewhat  above  the 
joint,  it  passes  under  the  tendon  of  the  tibialis  anticus, 
and  is  distributed  to  the  internal  ancle,  and  the  con- 
tiguous part  of  the  foot. 

4.  The  External  Malleolar,  (Malleolaris  Ex- 
terna) exists  most  commonly  as  two  small  branches,  one 
arising  on  a level  with  the  joint,  and  the  other  an  inch 
or  two  above.  They  pass  beneath  the  tendons  of  the 
extensor  longus  and  the  peroneus  tertius,  to  the  lower 
part  of  the  fibula,  and  inosculate  with  the  peroneal 
artery. 

5.  The  Tarsal  Artery,  (Arteria  Tarsea)  arises 
from  the  anterior  tibial  just  below  the  ancle  joint;  it 
runs  outwardly  under  the  tendons  and  the  belly  of  the 
extensor  brevis,  to  be  distributed  to  the  upper  outer 
part  of  the  tarsus. 

6.  The  Metatarsal  Artery,  (Arteria  Metatar- 
sea)  arises  just  below  the  last,  and  is  distributed  by 
many  branches  on  the  upper  part  of  the  metatai-sus. 
A successful  injection  demonstrates  a branch  in  each 
of  the  three  outer  interosseous  intervals  of  the  metatar- 
sal bones  above. 

7.  The  Dorsal  Artery  of  the  Great  Toe,  (Dor- 
salis Hallucis)  arises  from  the  anterior  tibial  at  the  root 


BLOOD  VESSELS. 


449 


of  the  first  metatarsal  bone^  it  runs  in  the  superior  part 
of  the  first  metatarsal  interval,  and  terminates  in  two 
branches  which  go  to  the  opposed  faces  of  the  great 
toe,  and  the  second  toe. 

After  this  the  anterior  tibial  artery  sinks  down  and 
joins  the  external  plantar  in  the  sole  of  the  foot. 

The  Posterior  Tibiae  Artery,  (Arteria  Tibialis 
Postica)  extends  from  the  head  of  the  tibia  to  the  hollow 
of  the  os  calcis ; it  is  on  the  tibial  side  of  the  leg,  and 
is  placed  between  the  soleus  posteriorly,  and  the  flexor 
digitorum  anteriorly,  and  beneath  the  fascia  of  the 
part.  It  is  distributed  in  the  following  manner : 

1.  The  Peroneal  Artery,  (Arteria  Peronea) 
arises  a little  below  the  commencement  of  the  posterior 
tibial,  and  is  extended  from  the  inferior  edge  of  the 
popliteus  muscle  to  the  external  ancle.  It  is  placed 
at  the  tibial  edge  of  the  fibula,  between  the  flexor 
longus  pollicis  muscle,  and  the  external  edge  of  the 
tibialis  posticus.  Its  situation  is  therefore  deep  and 
of  difficult  access  in  the  living  body.  After  des- 
cending along  two-thirds  of  the  fibula,  it  divides  into 
anterior  and  posterior  branch.  The  first  traverses  the 
interosseous  ligament,  and  descending  in  front  of  it,  is 
ramified  on  the  upper  external  part  of  the  foot.  The 
second  descends  posteriorly  along  the  fibula,  and  is  dis- 
tributed about  the  peroneo-tibial  articulation  and  the 
adjacent  'parts. 

3 L 


450 


OF  THE  LOWER  EXTREMITIES. 


2.  Several  small  irregular  muscular  and  cutaneous 
branches  afterwards  arise  from  the  posterior  tibia), 
and  at  its  upper  part  most  commonly,  the  Arteria  Nutri- 
tia  Tibiae. 

At  the  ancle  the  posterior  tibial  is  at  tlie  internal 
edge  of  the  tendo  achillis,  and  still  confined  by  the 
fascia  of  the  part.  It  passes  to  the  sole  of  the’  foot  in 
the  hollow  of  the  os  calcis,  between  the  bone  and  the 
abductor  muscle  of  the  great  toe.  At  the  ancle  it  is  on 
aline  with  the  internal  margin  of  the  joint  behind,  and 
in  {contact  with  the  posterior  malleolus,  between  the 
tendon  of  the  flexor  longus  pollicis,  and  that  of  the 
flexor  longus  digitorum.  Having  got  to  the  sole  of  the 
foot  it  terminates  by  dividing  into  two  branches,  the 
Internal  and  External  Plantar  Arteries. 

The  Internal  Plantar,  (Arteria  Plantaris  Inter- 
na,) is  the  smaller  of  the  two;  it  is  covered  by  the 
abductor  pollicis,  and  passing  between  it  and  the  in- 
ternal inferior  margin  of  the  foot,  it  terminates  at  the 
anterior  end  of  the  first  metatarsal  bone  in  the  internal 
digital  artery  of  the  great  toe.  In  this  course  it  sends 
several  branches  to  the  contiguous  parts,  which  give 
them  a high  degree  of  vascularity.  One  of  the  most 
remarkable  is  given  off  about  the  os  scaphoides  and 
cruizes  along  the  internal  margin  of  the  abductor  pol- 
licis to  its  anterior  end.  Another  makes  its  appearance 
superficially  in  the  sole  of  the  foot,  in  the  fissure  be- 


BLOOD  VESSELS. 


451 


tween  the  abductor  pollicis  and  the  flexor  brevis  digi- 
toruin,  and  goes  as  far  forward  as  the  other. 

The  External  Plantar,  (Arteria  Plantaris  Ex- 
terna, ) inclines  towards  the  outer  margin  of  the  foot, 
between  the  flexor  brevis  digitorum  and  the  flexor 
accessorius;  it  then  advances  at  the  internal  edge  of  the 
abductor  minimi  digiti  to  the  root  of  the  metatarsal 
bone  of  the  fourth  toe,  and  makes  a curvature  forwards 
and  inwards  between  the  tendons  of  the  flexor  longus 
and  the  metatarsal  bones,  to  the  first  metatarsal  interval, 
where  it  is  joined  by  the  anterior  tibial  artery  from 
above.  This  sweep  forms  the  plantar  arch  (arcus 
plantaris. ) The  distribution  of  the  external  plantar  is 
as  follows: 

a.  Half  an  inch  from  its  origin  it  detaches  back- 
wards and  outwards  to  the  inferior  and  to  the  external 
parts  of  the  heel  a multifidous  branch,  which  also  sends 
an  arteriole  along  the  external  edge  of  the  abductor 
minimi  digiti. 

i.  At  the  root  of  the  fourth  metatarsal  bone  a branch 
arises,  called  the  External  Plantar  Artery  of  the  Little 
Toe,  which  goes  first  along  the  internal  margin  of  the 
muscles  of  this  organ,  and  afterwards  at  the.  head  of  its 
metatarsal  bone,  gets  between  them  and  the  bone,  and 
is  distributed  along  the  external  margin  of  the  little 
toe. 

c.  The  Digital  Arteries  come  next,  which  arise  suc- 
cessively at  the  fourth,  third,  second,  and  first  meta- 


452 


OF  THE  LOWER  EXTREMITIES. 


tarsal  iritervals,  or  near  them,  from  the  convex  side  of 
the  plantar  arch.  They  get  forward  between  the 
transversalis  pedis  and  the  interosseous  muscles,  and, 
arriving  at  the  roots  of  the  toes,  each  artery  bifurcates 
and  goes  to  the  opposed  sides  of  the  adjacent  toes,  like 
the  corresponding  arteries  of  the  hand. 

The  digital  artery  that  supplies  the  great  toe  and 
the  opposite  side  of  the  toe  next  to  it,  is  derived  from 
the  united  trunks  of  the  anterior  tibial  and  the  external 
plantar.  At  the  head  of  the  metatarsal  bone  it  de- 
taches a branch  which  runs  along  the  inner  edge  of  the 
great  toe,  and  is  united,  by  anastomoses,  with  the  in- 
ternal plantar  artery. 

Of  the  Veins  of  the  Lower  Extremities. 

These  veins  are  superficial  and  deep-seated.  The 
more  important  of  the  first  are  the  Saphena  Magna  and 
the  Minor. 

1.  The  Saphena  Magna  arises  from  the  inside  of 
the  foot,  about  the  great  toe,  and  from  its  sole ; it  passes 
in  front  of  the  internal  ancle,  along  the  inside  of  the 
leg,  over  the  internal  condyle  of  the  femur,  along  the 
inner  front  part  of  the  thigh,  and  terminates  in  the  fe- 
moral vein  just  below  Poupart’s  ligament.  As  it  as- 
cends it  collects  branches  from  the  anterior  and  pos- 
terior parts  of  the  lower  extremity.  It  may  be  seen 
very  readily  in  the  living  subject  beneath  the  skin. 


BLOOD  VESSELS. 


453 


2.  The  Saphena  Minor  is  also  readily  seen  through 
the  skin.  It  arises  from  the  external  superior  parts  of 
the  foot,  passes  behind  the  external  ancle,  and  ascends 
on  the  outside  of  the  leg  to  the  ham,  receiving  contri- 
butions in  its  course;  here  it  crosses  the  external  head 
of  the  gastrocnemius  muscle,  and,  dipping  into  the 
ham,  empties  into  the  popliteal  vein. 

Frequent  anastomoses  occur  between  the  saphena 
magna  and  minor. 

The  origin  and  course  of  the  femoral  veins  are  so 
similar  to  the  distribution  and  course  of  the  femoral 
Artery,  that  a description  is  needless.  A venous  tube 
always  attends  an  arterial  one,  being  in  contact  with 
it,  enclosed  in  the  same  sheath,  and  called  by  the  same 
name.  The  smaller  arterial  branches  in  the  leg  and 
thigh  have  each  two  veins  called  Venae  Comites. 

The  relative  situation  of  the  large  venous  trunks  is 
important.  At  Poupart’s  ligament  the  femoral  vein 
is  at  the  inside  of  the  artery;  at  the  passing  of  the 
adductor  tendon,  the  vein  is  nearest  the  thigh  bone ; 
and  in  the  ham,  the  popliteal  vein  is  behind  the  artery 
and  consequently  more  superficial. 


454 


OF  THE  LOWER  EXTREMITIES. 


Section  IV. 

Of  the  JVerves  of  the  Lower  Extremities. 

The  Nerves  of  the  Lower  Extremity  are  derived 
from  that  part  of  the  medulla  spinalis  which  is  situated 
in  the  lumbar  vertebrae  and  in  the  sacrum.  The 
lumbar  nerves  form  a plexus  behind  the  psoas  magnus 
muscle,  from  which  proceeds  a cluster  of  nerves  to 
supply  the  front  part  of  the  lower  extremity,  including 
both  its  skin  and  muscles.  The  sacral  nerves  form  a 
plexus  in  the  pelvis  at  the  side  of  the  rectum,  from 
which  proceeds  the  largest  nerve  in  the  body,  the 
Sciatic,  appropriated  to  the  supply  of  the  skin  and 
muscles  on  the  back  part  of  the  lower  extremity.  The 
lower  part  of  the  lumbar  plexus  is  continued  into  the 
upper  of  the  sciatic  or  sacral,  so  that,  under  a more 
general  classification  than  what  is  adopted,  both  of 
these  plexuses  may  be  considered  as  forming  but  one. 

The  Plexus  Lumbalis  is  seen  by  dissecting  the 
psoas  magnus  muscle  from  its  origin  and  turning  it 
aside;  the  primitive  nerves,  constituting  this  plexus, 
sometimes  pass  through  the  substance  of  the  muscle 
instead  of  going  behind  it.  The  plexus  is  formed  by 
the  four  upper  lumbar  nerves  with  a filament  from  the 
last  dorsal.  The  anterior  branches  only  of  these  nerves 


NERVES. 


455 


are  concerned  in  forming  it,  as  the  posterior  bran- 
ches all  go  to  the  muscles  of  the  back. 

In  the  distribution  of  this  plexus  to  the  lower  ex- 
tremity, it  will  be  seen,  shortly  after  the  commence- 
ment of  the  dissection,  that  its  branches  may  be  con- 
sidered under  two  divisions ; first,  such  as  go  to  the 
skin,  and  secondly,  such  as  go  to  the  muscles. 

From  the  upper  part  of  the  plexus,  fibrillce  pass  out- 
wards and  downwards  over  the  quadratus  muscle;  some 
of  their  ramuscules  are  spent  on  the  sides  of  the  ab- 
dominal muscles ; others  wind  over  the  crista  of  the 
ilium  about  its  middle  part  and  are  distributed  to  the 
integuments  of  the  hip. 

The  Spermaticus  Externus  arises  also  from  the 
upper  part  of  this  plexus ; it  crosses  the  iliacus  inter- 
nus  muscle,  shaping  its  course  towards  the  anterior 
superior  spinous  process  of  the  ilium.  Here  it  involves 
itself  in  the  edge  of  the  abdominal  muscles,  and,  go- 
ing on  the  posterior  face  of  Poupart’s  ligament,  at  the 
internal  abdominal  ring  it  joins  the  spermatic  cord  of 
the  male,  or  the  round  ligament  of  the  uterus  of  the 
female.  In  the  first  case  it  is  distributed  to  the  sper- 
matic cord  and  scrotum;  in  the  second  to  the  labia  ex- 
terna and  mons  veneris. 

The  CuTANEUS  Externus  arises  from  the  lumbar 
plexus  below  the  external  spermatic.  It  passes  across 


456 


OF  THE  LOWER  EXTREMITIES. 


the  illacus  internus  towards  the  anterior  superior  spi- 
nous process  about  an  inch  below  the  spermaticus 
externus,  and  crosses  the  latter  nerve  just  at  that  pro- 
cess. Emerging  from  the  abdomen,  by  penetrating 
the  commencement  of  Poupart’s  ligament,  it  is  distri- 
buted, in  several  branches,  to  the  integuments  of  the 
vastus  externus  muscle  and  along  the  edge  of  the 
rectus  femoris ; one  of  the  latter  extends  to  the  pa- 
tella. 

The  CuTANEUS  Medius  is  given  from  the  anterior 
crural,  an  inch  or  so  above  Poupart’s  ligament,  com- 
ing from  it,  among  the  cluster  of  branches  which  arise 
there  to  be  distributed  to  the  iliacus  internus  muscle 
and  to  the  muscles  of  the  thigh.  It  appears  superfi- 
cially on  the  thigh,  for  the  first  time,  by  penetrating 
the  sartorius  muscle,  about  the  internal  edge  of  the 
rectus  femoris ; it  descends  then  along  the  same  edge 
of  the  latter  muscle,  and  is  distributed  to  its  integu- 
ments. It  does  not  descend  so  low  as  the  other  nerve. 

The  CuTANEUs  Anterior  arises  also  from  the  cru- 
ral nerve ; it  is  on  the  inner  side  of  the  cutaneous  me- 
dius, emerges  from  the  fascia  of  the  thigh,  and  crosses 
the  sartorius  muscle  two  or  three  inches  below  the 
cutaneus  medius.  It  is  distributed  on  the  integuments 
of  the  vastus  internus  muscle,  and  some  of  its  branches 
extend  to  the  internal  edge  of  the  patella. 


NERVES. 


457 


The  CuTANEUs  Internus  arises  from  the  anterior 
crural  nerve  among  the  same  cluster  above  Poupart’s 
ligament.  It  divides  into  four  or  five  branches  of 
different  lengths,  and  is  distributed  to  the  integu- 
ments of  the  adductor  muscles  and  along  the  inner 
front  side  of  the  thigh.  One  branch  observes,  very 
much,  the  course  of  the  tendon  of  the  adductor 
magnus,  and  reaches  as  far  down  as  the  inner  side  of 
the  knee. 

The  Cruralis  Anterior  arises  from  the  middle 
nerves  of  the  lumbar  plexus;  at  first  it  is  beneath  the 
psoas  magnus  muscle ; it  then  gets  to  its  outside  and 
passes  from  the  abdomen,  under  Poupart’s  ligament, 
about  half  an  inch  from  the  exterior  margin  of  the  femo- 
ral artery.  Before  it  reaches  Poupart’s  ligament  it  gives 
off  a cluster  of  nerves,  several  of  which  go  to'  the  iliacus 
internus  muscle,  others  form  superficial  or  cutane- 
ous nerves  of  the  thigh„  and  others  deep-seated  or 
muscular  branches.  The  distribution  of  the  cutaneous 
nerves  has  just  been  mentioned;  the  muscular  ones 
supply  the  adductor  muscles,  the  four  extensors,  the 
pectineus,  the  sartorius,  and  the  gracilis. 

One  of  the  branches  of  the  anterior  crural  nerve  is 
seen  to  accompany  the  femoral  artery,  till  the  artery 
penetrates  the  adductor  magnus ; it  then  runs  along  the 
front  margin  of  the  tendon  of  the  adductor  magnus,  in  a 
channel  formed  by  this  tendon  and  the  origin  of  the 
vastus  internus.  The  nerve  alluded  tQ  is  the  Saphe- 


458 


OF  THE  LOWER  EXTREMITIES. 


nusj  it  passes  afterwards  between  the  internal  condyle 
of  the  femur  and  the  sartorius  muscle,  attaches  itself  to 
the  saphena  vein,  and  is  distributed  to  the  integuments 
of  the  inner  side  of  the  leg  and  of  the  upper  internal 
parts  of  the  foot. 

The  Nervus  Obturatorius  is  derived  from  the 
middle  of  the  lumbar  plexus,  also,  and  has  very  much 
the  same  position  in  regard  to  the  psoas  magnus  as  the 
anterior  crural  nerve.  It  descends  from  beneath  the 
psoas  magnus  into  the  pelvis,  near  the  sacro-iliac  suture, 
and  passes  forwards  and  downwards  to  the  obturator 
foramen,  having  got  through  which,  it  divides  into  an 
anterior  and  a posterior  branch.  The  first  is  distri- 
buted to  the  heads  of  the  adductor  longus  and  brevis, 
and  to  the  gracilis  and  integuments.  The  second  ter- 
minates in  the  obturator  externus,  and  the  adductor 
magnus. 

The  Sciatic  Plexus,  (Plexus  Ischiadicus)  is  formed 
by  the  union  of  the  last  lumbar  with  the  four  upper 
sacral  nerves;  the  last  lumbar,  before  it  joins  the 
plexus,  receives  the  branch  of  the  fourth  lumbar  nerve, 
which  is  left  after  the  lumbar  plexus  is  formed.  This 
plexus  is  situated  at  the  side  of  the  rectum  before  the 
pyriformis  muscle. 

The  sacral  nerves  amount  to  six  in  number,  some- 
times only  to  five.  They  arise  from  the  lower  part  of 
the  cauda  equina,  and  pass  in  a very  oblique  direction 


NERVES. 


459 


in  order  to  arrive  at  the  sacral  foramina.  Like  the  other 
nerves  of  the  spine  they  form  ganglions  by  the  union 
of  their  anterior  and  posterior  fasciculi,  and  then  pass 
outwards  from  the  spinal  canal,  each  one  by  an  an- 
terior branch  which  goes  through  the  foramen  in  front 
of  the  sacrum,  and  a posterior  branch  much  smaller, 
which  gets  through  the  foramen  on  the  back  of  the 
sacrum.  The  volume  of  the  posterior  branches  in- 
creases till  the  fourth,  but  the  fifth  and  the  sixth  are 
much  smaller,  in  fact  only  fibrillse.  These  posterior 
branches  all  communicate  with  each  other,  being  dis- 
tributed to  the  head  of  the  sacro-lumbalis  and  lon- 
gissimus  dorsi,  to  the  posterior  edge  of  the  gluteus 
magnus,  to  the  integuments  of  the  buttock,  margin  of 
the  anus,  and  to  the  internal  parts  of  the  thigh. 

The  anterior  branches  of  the  sacral  nerves  are  much 
larger  than  the  posterior.  The  four  first  communi- 
cate with  the  sacral  ganglions  of  the  great  sympathetic, 
besides  forming  the  ischiatic  plexus.  The  third  and 
the  fourth,  assisted  by  the  sympathetic,  form  the  hypo- 
gastric plexus.  The  fifth,  and  the  sixth  when  it  ex- 
ists, are  distributed  to  the  coccygeus,  sphincter,  and 
levator  ani.'^ 

* This  is  only  given  as  the  most  frequent  arrangement  of  the 
sciatic  plexus,  and  of  the,  branches  of  nerves  which  proceed  from 
it;  other  arrangements  will  often  be  met  with  in  the  cavity  of 
the  pelvis,  in  which  not  so  many  sacral  nerves  are  sent  to  the 
plexus,  and  the  several  branches  proceeding  from  it,  depart  in 
a different  manner. 


460 


OF  THE  LOWER  EXTREMITIES. 


The  following  small  branches  are  sent  from  the 
Sciatic  Plexus:^" 

a.  Nervi  Glutsei,  one  passing  through  the  upper  part 
of  the  sciatic  notch  along  with  the  artery  to  the  glutseus 
medius  and  minimus,  the  other  below  the  pyriformis 
muscle  to  the  glutaeus  magnus. 

h.  Nervus  Pudendalis  Longus  Inferior,  which  passes 
under  the  tuber  of  the  ischium  to  the  glutseus  magnus, 
perineal  muscles,  urethra  and  integuments  of  the  penis, 
and  scrotum  in  men,  and  to  the  inferior  parts  of  the 
labia  externa  in  women. 

c.  Ramus  Feraoralis  Cutaneus  Posterior.  This 
nerve  is  placed  between  the  integuments  of  the  thigh, 
and  the  muscles  which  arise  from  the  tuberosity  of 
the  ischium.  It  sends  many  branches  successively  to 
the  skin  on  the  back  of  the  thigh;  one  of  its  branches 
longer  than  the  others  goes  down  to  the  ham,  and  there 
divides  into  several  filaments  which  are  distributed  to 
the  integuments  on  the  back  of  the  leg. 

TheNERvus  Pudexdalis  Superior  comes  from  the 
third  and  fourth  sacral,  occasionally  receiving  a contri- 
bution from  the  small  sciatic  when  it  exists.  It  goes  in 
company  with  the  internal  pudic  artery  between  the  sa- 
cro-sciatic  ligaments,  and  then  divides  into  two  bran- 
ches; the  inferior  of  which  is  distributed  to  the  in- 

* They  sometimes  come  from  a common  trunk  called  the 
small  sciatic. 


NERVES. 


461 


teguments  and  muscles  of  the  perineum,  to  the  urethra 
and  scrotum ; the  superior  passing  along  the  ramus  of 
the  ischium  and  pubes  with  the  trunk  of  the  internal 
pudic  artery,  is  distributed  to  the  obturator  internus, 
accelerator  urinas,  urethra,  and  afterwards  getting 
between  the  symphysis  of  the  pubes  and  the  penis, 
terminates  on  its  integuments  and  the  glans  penis. 

The  Nervus  Ischiadicus,  or  the  Great  Sciatic,  is 
the  common  trunk  formed  from  the  sciatic  plexus ; it 
is  much  the  largest  nerve  in  the  body,  and  passes  from 
the  pelvis  between  the  pyriformis  and  the  geminus 
superior.  It  crosses  vertically  behind  the  small  rotator 
muscles  of  the  thigh,  being  concealed  by  the  inferior 
edge  of  the  glutseus  magnus ; it  is  there  about  half-way 
between  the  tuberosity  of  the  ischium  and  the  trochanter 
major.  Thence  it  descends  on  the  back  of  the  adduc- 
tor magnus  at  the  outer  edge  of  the  long  head  of  the 
biceps  flexor  cruris.  About  half-way  down  the  thigh, 
sometimes  a little  lower,  the  Sciatic  nerve  divides  into 
the  Popliteal  or  Posterior  Tibial,  and  Peroneal  nerves. 
Occasionally  this  division  takes  place  as  high  as  the  exit 
of  the  nerve  from  the  pelvis,  but  in  this  case  the  fasci- 
culi are  parallel  with  each  other  as  far  as  the  middle 
of  the  thigh.  From  the  trochanter  minor  to  its  usual 
place  of  division,  this  nerve  is  parallel  with,  and  on  the 
back  of  the  thigh  bone,  but  there  the  two  branches 
begin  to  diverge.  The  popliteal  nerve  continues 
straight  downwards  to  the  back  and  middle  of  the  knee 


462 


OF  THE  LOWER  EXTREMITIES, 


joint,  and  to  the  interstice  between  the  heads  of  tlie 
gastrocnemii  muscles,  whereas  the  fibular  nerve  goes 
along  the  inner  posterior  edge  of  the  biceps  flexor 
cruris,  and  passes  between  its  tendinous  insertion  and 
the  external  head  of  the  gastrocnemius  muscle. 

In  this  course  the  following  branches  are  sent  fronj 
the  sciatic : Twigs  to  the  little  rotator  muscles  of  the 
thigh.  The  Cutaneus  Internus  Superior,  which  arises 
near  the  upper  part  of  the  thigh,  and  is  distributed  to 
the  skin  of  the  corresponding  part.  The  Cutaneus 
Internus  Inferior,  which  arises  just  below  the  last,  and 
descending  upon  the  inner  head  of  the  gastrocnemius 
externus,  is  distributed  to  the  integuments  of  the  calf 
of  the  leg.  A large  trunk,  and  sometimes  instead  of 
it,  distinct  branches  which  go  to  the  Adductor  Magnus, 
Semimembranosus,  Biceps  and  Semitendinosus. 

The  Peroneal  Nerve,  (Nervus  Peroneus)  at  the 
head  of  the  fibula  divides  into  two  branches,  the  Pe- 
roneus Externus  and  the  Tibialis  Anterior:  but  before 
this  division  it  sends  a small  branch  to  the  external 
parts  of  the  knee  joint,  and  two  cutaneous  branches 
called  Peroneo-Cutaneus.  The  internal  of  the  two 
latter  descends  behind  the  external  head  of.  the 
gastrocnemius,  and  at  the  bottom  of  the  leg  is 
united  to  a division  of  the  posterior  tibial  called  the 
External  Saphenus  or  Coramunicans  Tibiae.  The  ex- 


. NERVES. 


463 


ternal  branch  of  the  peroneo-cutaneous  is  distributed 
to  the  skin  along  the  fibula. 

The  External  Peroneal  Nerve,  (Peroneus  Exter- 
nus)  gets  between  the  head  of  the  peroneus  longus 
and  the  fibula,  then  between  the  peroneus  longus  and 
the  extensor  longus  digitorum ; it  descends  at  the  outer 
edge  of  the  last  muscle  to  the  inferior  third  of  the  leg, 
giving  out,  in  the  mean  time,  many  muscular  branches. 
Here  it  penetrates  the  aponeurosis  and  divides  into 
subcutaneous  branches,  which  supply  the  lower  part 
of  the  leg  and  the  upper  surface  of  the  foot  and  toes. 
This  nerve  is  called,  by  the  French,  the  Musculo  Cu- 
taneous of  the  leg. 

The  Anterior  Tibial  Nerve,  (Tibialis  Anterior)  gets 
obliquely  between  the  fibula,  the  peroneus  longus, 
and  the  extensor  longus  digitorum  to  the  front  of  the 
interosseous  ligament,  where  it  accompanies  the  ante- 
rior tibial  artery.  It  passes  with  the  artery  under  the 
annular  ligament  of  the  ancle,  and  has  its  terminating 
filaments  going  to  the  muscles  and  integuments  of  the 
upper  surface  of  the  foot  as  far  as  the  end  of  the  two 
first  toes.  One  of  its  branches  sinks  down  with  the 
anterior  tibial  artery  to  the  sole  of  the  foot.  High  up 
in  the  leg  it  gives  filaments  to  the  knee  joint,  and,  in 
its  course  downwards,  it  furnishes  the  muscles  on  the 
front  pf  the  leg. 

The  Popliteal  Nerve,  (Nervus  Popliteus)  having 
the  direction  mentioned,  is  placed  between  the  skin 


464 


OF  THE  LOWER  EXTREMITIES. 


and  the  popliteal  vein.  It  gets  between  the  heads  of 
gastrocnemii  muscles  and  perforates  the  origin  of  the 
soleus,  going  with  the  posterior  tibial  artery  between 
this  muscle  and  the  flexor  longus  digitorum  to  the 
bottom  of  the  leg.  It  gives  off 

a.  The  External  Saphenus,  (Saphenus  Externus  or 
Coramunicans  Tibiae)  which  arises  above  the  knee 
joint,  and,  descending  between  the  skin  and  the  gas- 
trocnemius, turns  ^outwardly  and  anastomoses  with 
the  cutaneous  branch  alluded  to  of  the  peroneal  nerve. 
The  common  trunk  passes  behind  the  external  ancle, 
along  the  external  margin  of  the  foot,  and  terminates 
on  the  two  last  toes,  having  given  off  a great  number 
of  cutaneous  branches. 

h.  Branches  to  the  heads  of  the  gastrocnemius, 
- soleus,  plantaris,  and  popliteus. 

c.  Branches  to  the  flexor  longus  digitorum,  tibialis 
posticus,  and  to  the  flexor  longus  pollicis  pedis. 

d.  A branch  through  the  interosseous  ligament  above 
to  the  tibialis  anticus. 

e.  At  the  inferior  part  of  the  leg  many  cutaneous 
.filaments,  one  of  which  gets  to  the  sole  of  the  foot. 

The  Posterior  Tibial  Nerve,  having  given  off  these 
branches,  divides  in  the  hollow  of  the  os  calcis  into 
Internal  and  External  Plantar  Nerves. 

The  Internal  Plantar,  (Plantaris  Internus)  pro- 
ceeds along  side  the  tendon  of  the  flgxor  muscle  of  the 


NERVES. 


465 


great  toe  and  the  flexor  longus,  and  gives  filaments  to 
the  contiguous  muscles.  It  then  divides  in  such  a way 
as  to  furnish  the  two  sides  of  the  three  first  toes  and, 
the  internal  side  of  the  fourth. 

The  External  Plantar,  (Plantaris  Externus) 
proceeds  with  the  artery  of  the  same  name  to  the 
outer  edge  of  the  foot  between  the  flexor  brevis  digi- 
torum  and  the  flexor  accessorius.  It  is  distributed  to 
the  two  sides  of  the  little  toe  and  to  the  external  side 
of  the  fourth  toe.  One  branch  penetrates  to  the  in- 
terosseous muscles  and  to  the  transversalis  pedis.  A 
branch  of  considerable  size  is  detached  near  the  heel 
to  the  muscles  and  integuments  connected  with  the 
os  calcis. 


PART  IV. 


CHAPTER  I. 

Of  the  Ligaments. 


Section  I. 

Of  the  Ligaments  of  the  Head  and  Spine. 

Articulation  of  the  Lower  Jaw.  The  condyle 
of  the  lower  jaw  is  invested  by  a capsular  ligament 
which  arises  from  the  margin  of  the  glenoid  cavity  of 
the  temporal  bone,  and  the  front  edge  of  its  tubercle, 
and  is  inserted  into  the  place  where  the  condyle  and 
neck  of  the  lower  jaw  unite.  This  ligament  has 
an  accumulation  of  fibres  internally  and  externally, 
which  gives  the  joint  the  appearance  of  lateral  liga- 
ments. 

By  cutting  open  the  capsular  ligament,  we  shall  see 
that  a moveable  cartilage  is  interposed  between  the 
glenoid  cavity  and  the  condyle,  having  its  upper  and 
under  surfaces  accommodated  to  the  opposite  articu- 
lar surfaces  of  these  parts.  There  are  also  two  dis- 


HEAD  AND  SPINE. 


467 


tinct  synovial  membranes,  one  passing  from  the  move- 
able  cartilage  to  the  glenoid  cavity,  and  the  other  from 
the  lower  surface  of  the  cartilage  to  the  Condyle.  The 
moveable  eartilage  is  also  attached  by  its  circumference 
to  the  internal  face  of  the  capsular  ligament. 

The  Stylo  Maxillary  Ligament  is  seen  here, 
which  runs  from  the  styloid  process,  to  the  angle  of  the 
lower  jaw,  where  it  is  inserted  between  the  masseter 
and  the  internal  pterygoid  muscles.  Also  a small 
round  ligament  which  goes  from  the  styloid  process  to 
the  appendix  of  the  os  hyoides. 

The  Ligaments  of  the  Spine. 

There  is  a capsular  ligament  with  its  synovial  mem- 
brane, which  surrounds  on  either  side  the  superior  ob- 
lique process  of  the  first  vertebra,  and  is  inserted  into 
the  root  of  the  corresponding  condyle  of  the  os  occipitis. 

A circular  ligament  arises  from  the  whole  superior 
margin  of  the  first  vertebra,  and  is  inserted  into  the 
margin  of  the  great  occipital  foramen. 

The  Occipito-Dentatum  Ligament  passes  from  the 
point  of  the  processus  dentatus,  and  is  inserted  into 
the  anterior  part  of  the  margin  of  the  occipital 
foramen. 


468 


OF  THE  LIGAMENTS. 


The  two  Moderator  or  Lateral  Ligaments,  one  on 
each  side,  arise  from  the  lateral  margin  of  the  proces- 
sus dentatus;  and  are  inserted  into  the  corresponding 
surfaces  of  the  first  vertebra,  and  into  the  inner  margin 
of  the  foramen  magnum. 

The  Transverse  Ligament  subtends  the  cavity  in 
the  first  vertebra  for  the  reception  of  the  processus 
dentatus.  The  upper  edge  of  this  ligament  is  fi_\ed 
to  the  foramen  magnum  and  the  lower  edge  into  the 
root  of  the  processus  dentatus.  It  keeps  this  process 
in  its  place. 

On  each  side  there  is  a loose  capsular  ligament 
with  its  synovial  membrane  passing  between  the  con- 
tiguous oblique  processes  of  the  first  and  second  ver- 
tebrsB. 

Between  the  bodies  of  all  the  vertebrae  except  the 
first  and  second,  a ligamento-cartilaginous  matter  is 
placed,  which  is  fixed  to  their  bodies,  and  is  a very 
potent  means  of  union.  This  substance  is  more 
fibrous  and  hard  externally,  but  near  its  centre  it  is 
of  a pulpy  consistence.  A horizontal  cut  seems  to 
demonstrate  it  as  formed  of  concentric  fibres,  but  there 
are  also  many  others  whose  course  is  oblique,  and 
irregular.  The  central  pulpy  part  is  confined  by 
the  other,  and  also  in  a state  of  compression,  it  makes 


HEAD  AND  SPINE. 


469 


an  articulation  in  some  degree  equivalent  to  the  ball 
and  socket  joint. 

The  Anterior  Vertebral  Ligament  extends  from  the 
second  vertebra  to  the  sacrum.  It  consists  of  longi- 
tudinal white  fibres,  and  is  placed  on  the  convex  fore 
part  of  the  spine.  It  adheres  very  closely  to  the 
intervertebral  substance,  and  sends  olf  processes  on 
each  side  to  fix  it  more  securely  to  the  bodies  of  the 
vertebrae.  Where  much  motion  is  admitted,  as  in  the 
neck  and  the  loins,  it  is  thinner  than  on  the  dorsal 
vertebrae. 

The  Posterior  Vertebral  Ligament  is  in  the  spinal 
cavity.  It  arises  from  the  edge  of  the  foramen  mag- 
num, and  passes  down  to  the  sacrum  on  the  posterior 
surface  of  the  bodies  of  all  the  vertebrae,  adhering  to 
them  and  to  the  intervertebral  substance.  It  is  nar- 
rower on  the  bodies  of  the  vertebrae  than  on  the  inter- 
vertebral substance. 

The  Yellow  Ligaments;  there  are  twenty-three 
pairs  of  them.  They  pass  between  the  adjoining  ver- 
tebrae; one  on  each  side,  between  the  spinous  and  ob- 
lique process;  and  are  best  seen  from  the  inside  of  the 
vertebral  cavity.  The  first  pair  passes  from  the  bony 
bridge  of  the  second  vertebra  to  that  of  the  third, 
and  so  on  successively  to  the  sacrum.  They  are  very 
elastic. 


470 


OF  THE  LIGAMENTS. 


Ligamentous  fibres  pass  also  between  the  spinous 
processes,  and  there  are  others  between  the  transverse 
processes. 

The  Ligamentum  Nuchse  is  a tendinous  septum  be- 
ginning at  the  spinous  process  of  the  seventh  cervical 
vertebra,  and  running  up  to  the  occiput,  where  it  is 
fixed  into  its  vertical  ridge.  It  is  connected  intermedi- 
ately to  the  spinous  processes  of  all  the  vertebras  above 
the  seventh,  so  that  it  forms  a partition  between  the 
muscles  of  the  two  sides  of  the  neck. 

All  the  Oblique  Processes  have  their  capsular  and 
synovial  membranes. 


Section  II. 

Ligaments  of  the  Thorax. 

The  heads  of  the  ribs  and  their  tubercles  are  fiu’- 
nished  with  capsular  and  synovial  membranes  uniting 
them  with  the  corresponding  articular  surfaces  of  tlie 
vertebrae,  and  admitting  of  motion. 

The  Ligamenta  Transversaria  Interna  arise  from 


THORAX. 


471 


the  inferior  surface  of  each  transverse  process  under 
its  articular  face  for  the  tubercle  of  the  rib,  and  are 
inserted  into  the  upper  margin  of  the  neck  of  the  rib 
below  j its  fibres  run  obliquely  inwards.  The  Liga- 
menta  Transversaria  Externa  are  behind  the  others  and 
pass  horizontally  between  the  points  of  the  transverse 
processes  and  the  upper  margin  of  the  back  of  the  ribs; 
beyond  their  tubercles,  their  fibres  go  obliquely  out- 
wards. 

The  Ligamenta  Cervicum  Costarum  are  concealed 
by,  and  pass  between  the  back  of  the  neck  of  the  rib, 
and  the  front  of  the  corresponding  transverse  process. 
To  be  seen  the  rib  must  be  sawed  through  in  its  length. 

At  its  anterior  extremity  there  is  a cavity  in  the  rib 
into  which  the  sternal  cartilage  fits  and  is  there  united. 
This  junction  is  strengthened  by  short  ligamentous 
fibres  surrounding  the  part  and  going  from  the  rib  to 
the  cartilage. 

The  cartilages  of  the  seven  true  ribs  run  into  pits 
in  the  sternum,  and  are  there  secured  by  the  radiated 
ligaments  which  lie  in  front  of  the  joint. 

The  Sternum  is  covered,  both  in  front  and  behind, 
by  a strong  ligamentous  expansion  adhering  very 
closely  to  it.  From  the  second  bone  of  the  sternum 
and  from  the  inferior  margin  of  the  seventh  true  rib, 


472 


OF  THE  LIGAMENTS. 


near  it,  ligamentous  fasciculi  are  sent  to  the  cartilage 
ensiformis. 


Section  III. 

Of  the  Ligaments  of  the  Pelvis. 

At  the  posterior  part  of  the  junction  of  the  ilium 
with  the  sacrum,  several  distinct  ligaments  are  found. 

The  Ilio  Lumbar  Ligament  is  stretched  from  the 
transverse  process  of  the  last  vertebra  of  the  loins  to 
the  posterior  superior  spinous  process  of  the  ilium  and 
the  adjoining  part  of  the  crista.  It  is  much  mixed 
with  fat.  Just  below  this  is  the  Ligamentum  Sacro- 
Spinosum,  which  is  extended  between  the  posterior 
superior  spinous  process  and  the  two  or  three  upper- 
most transverse  processes  of  the  sacrum. 

The  Sacro  Iliac  Ligament  is  an  assemblage  of  very 
short,  strong,  compact  fibres,  which  lie  on  tlie  back  of 
this  articulation.  It  is  connected  to  the  sacrum  by 
its  transverse  processes  and  by  the  rough  surface  just 
on  the  iliac  side  of  them,  and  to  the  ilium  by  the  rough 
edge  just  behind  its  articular  surface  with  the  sacrum. 


PELVIS. 


473 


In  front  also  tliis  articulation  is  covered  by  short,  strong 
fibres. 

The  Os  Coccygis  is  united  to  the  sacrum  by  inter- 
vertebral substance  and  also  by  longitudinal  ligaments 
on  its  front  and  back.  The  anterior  ligament  is  not 
very  distinct,  but  the  posterior  is,  as  it  arises  from  the 
inferior  margin  of  the  spinal  canal  of  the  sacrum,  and, 
contributing  to  finish  the  canal  or  to  close  it  up,  is 
then  distributed  on  the  back  of  the  os  coccygis  to  its 
extremity. 

The  foramina,  on  the  posterior  part  of  the  sacrum, 
are  much  diminished  by  ligamentous  fibres  which  pass 
in  every  direction. 

The  Posterior  Sacro  Sciatic  Ligament  arises  from 
the  inferior  posterior  spinous  process  of  the  ilium, 
from  the  side  of  the  sacrum  which  is  below  it,  and 
from  the  side  of  the  os  coccygis.  Its  fibres  converg- 
ing, it  becomes  thicker  in  the  middle,  and  is  inserted 
into  the  ridge  at  the  inner  margin  of  the  tuberosity  of 
the  ischium,  and  is  prolonged  towards  the  pubes  by  a 
continued  attachment  along  the  inner  margin  of  the 
ramus  of  the  ischium. 

The  Anterior  Sacro  Sciatic  Ligament  has  its  origin 
somewhat  confounded  with  that  of  the  posterior.  It 
arises  from  the  side  of  the  sacrum,  below  its  junction 
with  the  ilium,  and  from  the  upper  part  of  the  side  of 

3 o 


474 


OF  THE  LIGAMENTS. 


the  os  coccygis.  Its  course  is  more  horizontal  than 
that  of  the  posterior,  and  it  is  inserted  into  the  spinous 
process  of  the  ischium. 

The  articular  surfaces  of  the  sacrum  and  ilium  are 
covered,  each  with  its  appropriate  cartilage ; that  on 
the  sacrum  is  somewhat  thicker  than  the  one  on  the 
ilium.  The  contiguous  surfaces  of  these  cartilages  are 
rough,  and  are  separated  by  a yellow  half-fluid  tena- 
cious substance. 

The  Obturator  Ligament  closes  the  obturator  fora- 
men, and  arises  from  its  margin;  it  is  defective  .at  the 
superior  part  where  the  obturator  vessels  go  out.  It  is 
also  frequently  defective,  or  extremely  thin  below. 
The  obturator  muscles  arise  from  it. 

The  Ossa  Pubis  are  joined  together  by  a ligamento- 
cartilaginous  matter  which  fills  up  the  space  between 
them.  It  is  more  fibrous  externally,  and  is  there  form- 
ed of  concentric  lamellse  which  surround  the  articu- 
lation. In  men  there  is  more  of  this  fibrous  matter 
than  in  women ; in  the  latter,  one  frequently  finds  in 
the  posterior  part  of  the  symphysis,  a little  flat  oblong 
cavity  occasioned  by  a distinct  plate  of  cartilage  on 
each  bone.  This  cavity  is  moistened  by  a white  or 
yellowish  fluid. 

The  Sub-Pubic  Ligament  is  a strong  tendinous 


UPPER  EXTREMITIES. 


475 


membrane  of  half  an  inch  in  breadth,  occupying  the 
very  top  of  the  arch  of  the  pubes,  and  passing  from  one 
bone  to  the  other;  it  is  spoken  of  in  the  account  of  the 
fascise  of  the  pelvis. 

In  front  of  this  joint  there  are  several  other  fasci- 
culi of  fibres,  which  get  collectively  the  name  of  the 
Anterior  Pubic  Ligament. 


CHAPTER  II. 

Section  I. 

0/  the  Ligaments  of  the  Upper  Extremities. 

The  Clavicle  and  the  Sternum  are  very  firmly  united 
from  the  breadth  of  their  articulating  surfaces,  and  by 
the  thickness  of  their  ligaments.  The  Radiated  Liga- 
ment arises  from  the  front  of  the  internal  end  of  the 
clavicle,  and  is  inserted  around  the  margin  of  the  cor- 
responding part  of  the  articular  surface  of  the  sternum. 
The  Interclavicular  Ligament  lies  on  the  posterior  sur- 
face of  the  upper  end  of  the  sternum,  and  passes  from 
one  clavicle  to  the  other. 


476 


OF  THE  LIGAMENTS. . 


The  Capsular  Ligament  proceeds  from  around  fhe 
internal  end  of  the  clavicle,  and  is  inserted  into  the 
margin  of  the  articular  surface  of  the  sternum.  By 
cutting  it  open  we  find  that  there  is  a moveable  carti- 
lage interposed  between  the  two  bones,  connected  by 
its  margin  with  the  internal  surface  of  the  capsular 
ligament,  and  that  on  each  side  of  this  cartilage  there 
is  a distinct  synovial  membrane. 

The  Costo-Clavicular,  or  Rhomboid  Ligament,  arises 
from  the  cartilage  of  the  first  rib,  and  is  inserted  into 
the  tubercle  on  the  under  surface  of  the  clavicle,  near 
the  sternum. 

The  Scapulo-Clavicular  Ligaments  are  two  in  num- 
ber. The  first  is  a capsular  ligament  with  its  synovial 
membrane,  which  unites  the  acromial  end  of  the  clavi- 
cle to  the  acromion  process.  This  ligament  being 
thickened  above  and  below,  these  parts  are  called  the 
Superior  and  the  Inferior  ligaments;  occasionally  a 
moveable  cartilage  is  found  also  in  this  joint.  The 
second  ligament  is  the  Conoidal ; its  apex  arises  from 
the  tubercle  at  the  root  of  the  coracoid  process,  and  its 
base  is  inserted  into  the  tubercle  near  the  acromial  end 
of  the  clavicle.  From  the  outer  margin  of  the  conoid, 
a ligamentous  membrane,  called  the  Trapezoid  Liga- 
ment,. is  extended  to  the  acromial  end  of  the  clavicle. 


In  front  of  the  subclavius  muscle,  arising  from  the 


UPPER  EXTREMITIES. 


477 


root  of  the  coracoid  process  and  going  to  the  clavickj  is 
the  Ligamentum  Bicorne. 

The  Triangular  Ligament  of  the  Scapula  is  extend- 
ed over  the  shoulder  joint.  Its  basis  arises  from  the 
upper  margin  of  the  coracoid  process,  and  its  apex 
is  fixed  to  the  sternal  margin  of  the  acromion  beneath 
the  clavicle.  It  is  thinner  in  the  middle  than  at  either 
edge. 

The  Coracoid  Ligament  of  the  Scapula  is  stretched 
across  the  semilunar  notch,  and  converts  it  into  a 
foramen  for  the  vessels. 

Of  the  Shoulder  Joint. 

The  Scapulo-Humeral  Articulation  is  formed  by 
the  glenoid  cavity  of  the  scapula,  and  the  head  of  the 
os  humeri.  A capsular  ligament  arises  from  the  neck 
of  the  former,  and  is  inserted  into  the  neck  of  the  lat- 
ter. A fold  or  thickening  of  it  called  the  Accessary 
Ligament,  passes  from  the  coracoid  process  towards 
the  great  tuberosity  of  the  os  humeri. 

By  cutting  open  the  joint  we  see  the  synovial  mem- 
brane lining  its  cavity,  and  sending  a process  into  the 
groove  of  the  os  humeri,  which  is  afterwards  reflected 
along  the  tendon  of  the  biceps  in  such  a way  as  to  keep 
its  cavity  entire.  This  tendon  is  connected  with  the 
upper  margin  of  the  glenoid  cavity,  and  sends  on  each 


478 


OF  THE  LIGAMENTS. 


side  a fibrous  part  which  surrounds  the  margin  of  the 
cavity,  and  deepens  it. 

Of  the  Elbow  Joint. 

The  Elbow  Joint  has  a eapsular  ligament  arisiug 
from  the  margin  of  the  articular  surface  of  the  os  hu- 
meri, and  inserted  into  the  margin  of  the  articular 
surface  of  the  ulna,  and  into  the  coronary  ligament  of 
the  radius.  This  capsule  has  additional  fibres  inter- 
nally, and  externally,  called  Lateral  Ligaments,  or 
Brachio-Ulnar,  and  Brachio- Radial.  The  first  arises 
from  the  internal  condyle,  and  spreads  in  a radiated 
manner  to  be  inserted  into  the  inner  side  of  the  coro- 
noid  and  olecranon  process.  Tlie  second  arises  from 
the  external  condyle,  and  is  inserted  into  the  coronary 
ligament  of  the  radius. 

The  Coronary  Ligament  of  the  Radius  arises  from 
one  side  of  the  sigmoid  cavity  of  the  coronoid  pro- 
cess of  the  ulna,  and  surrounding  the  neck  of  the 
radius  it  is  inserted  into  the  other  side  of  tlie  same 
cavity.  Its  upper  margin  is  blended  with  the  capsu- 
lar ligament,  and  its  lower  is  loosely  attached  to  the 
root  of  the  neck  of  the  radius. 

On  the  anterior  and  posterior  surfaces  of  the  cap- 
sule of  the  elbow  joint,  there  are  small  and  irregular 
fibres,  termed  accessary  ligaments,  but  the  capsule  is 


UPPER  EXTREMITIES. 


479 


particularly  thin  under  them,  in  order  to  accommodate 
the  flexions  of  the  joint. 

By  cutting  open  the  eapsule  we  see  the  extent  of 
the  synovial  membrane,  and  the  eartilaginous  surfaces 
of  the  bones.  At  the  bottom  of  the  greater  sigmoid 
cavity  of  the  ulna,  a small  quantity  of  vascular  adi- 
pose matter  is  found. 

The  Interosseous  Ligament  fills  up  the  space  be- 
tween the  radius  and  the  ulna,  being  fixed  on  each 
side  to  their  sharp  edges.  It  is  composed  principally 
of  oblique  fibres  interwoven  with  each  other,  and  in 
it  are  several  perforations  for  blood-vessels.  One  par- 
ticularly large  is  just  at  the  tubercle  of  the  radius. 

There  is  a small  ligamentous  band  called  the  round 
ligament,  at  the  upper  part  of  the  opening  for  the  in- 
terosseous vessels,  going  from  the  base  of  the  coronoid 
process  to  the  lower  part  of  the  tubercle  of  the  radius 
and  called  the  round  ligament. 

Of  the-  Wrist  Joint. 

The  Wrist  Joint  is  formed  between  the  lower  ends 
of  the  radius  and  ulna,  and  the  three  first  bones  of  the 
upper  row  of  the  carpus.  A capsular  ligament  passes 
from  the  margin  of  the  cartilaginous  surface  of  the 
radius,  and  from  the  part  of  the  same  cartilage  which 


480 


OF  THE  LIGAMENTS. 


is  continued  between  the  ulna  and  the  cuneiform 
bone,  and  is  inserted  into  the  margin  of  the  articular 
head  formed  by  the  scaphoid,  lunar,  and  cuneiform 
bones. 

The  External  Lateral  Ligament  arises  from  the  sty- 
loid process  of  the  radius,  and  is  inserted  into  the 
scaphoid  bone.  The  Internal  Lateral  Ligament  arises 
from  the  styloid  process  of  the  ulna,  and  is  inserted 
into  the  inner  side  of  the  cuneiform  bone,  and  the  cor- 
responding part  of  the  anterior  ligament,  which  con- 
fines the  flexor  tendons. 

By  cutting  open  this  articulation  we  see  the  syno- 
vial membrane  of  the  part,  and  a fold  of  it  called  the 
Mucous  Ligament,  which  passes  from  between  the 
scaphoides  and  lunare  to  the  end  of  the  radius.  We 
also  see  the  cartilage  of  the  radius  projecting  between 
the  cuneiform  bone  and  the  head  of  the  ulna,  and 
forming  with  the  head  of  the  ulna,  a distinct  joint,  sur- 
rounded by  a capsule  called  the  Sacciform  Ligament. 

The  Articulation  between  the  first  and  the  second 
row  of  carpal  bones  is  performed  by  a capsular  liga- 
ment which  goes  from  the  first  to  the  second  row,  be- 
ing strengthened  laterally  by  a multiplication  of  its 
fibres,  constituting  lateral  ligaments  internally  and  ex- 
ternally. There  are  also  several  fasciculi  of  fibres 
which  run  in  varied  directions,  some  oblique  and  some 


UPPER  EXTREMITIES. 


481 


ti’ansverse,  fastening  the  two  rows  together  as  well  as 
the  individual  bones  of  the  same  row.  When  this 
joint  is  opened  we  find  but  one  synovial  membrane 
for  the  two  rows  of  bones  where  they  are  in  contact, 
and  this  membrane  sends  in  digital  processes  between 
the  lateral  surfaces  of  the  several  bones  which  are  op- 
posite to  each  other. 

There  are  strong  ligaments  which  go  from  the  car- 
pal to  the  bases  of  the  metacarpal  bones,  but  owing 
to  the  irregular  surfaces  of  these  bones  but  little  mo- 
tion is  allowed,  although  the  apparatus  of  articulation 
is  complete  with  its  capsular  ligaments  and  synovial 
membranes.  The  meta  -arpal  bone  of  the  little  finger 
has  more  motion  than  those  of  the  other  fingers;  the 
ring-finger  is  next^  the  middle  and  fore-fingers  are 
almost  stationary. 

The  Metacarpal  Bones  of  the  fingers  are  connected 
to  each  other  at  their  bases  by  transverse  ligamentous 
fasciculi ; they  are  also  connected  at  their  heads  in  the 
same  manner. 

A strong  capsular  ligament,  with  its  synovial  mem- 
brane, is  applied  to  the  articulation  between  the  tra- 
pezium and  the  thumb.  This  capsule  is  of  nearly  an 
uniform  thickness,  being  very  similar,  in  that  respect, 
to  the  capsule  of  the  shoulder  joint,  arid,  therefore, 
admits  of  every  variety  of  motion. 

3 p 


482 


OF  THE  LIGAMENTS. 


Between  the  heads  of  the  metacarpal  bones  and 
the  first  phalanges  there  is  a capsule  and  a synovial 
membrane.  The  eapsule  is  thickened  at  its  sides  by 
which  lateral  ligaments  are  formed.  In  front  it  has 
a eartilaginous  thickening  which  forms  a trochlea  for 
the  flexor  tendon.  Behind,  it  is  thin,  its  principal 
strength  being  derived  from  the  tendon  of  the  exten- 
sor muscle. 

The  Phalanges  are  articulated  in  the  same  way  with 
each  other  that  they  are  articulated  with  the  me- 
tacarpal bones. 


CHAPTER  IIL 
Sectiox  I. 

Ligaments  of  the  Inferior  Extremities. 

The  Hip  Joint  is  formed  by  the  acetabulum  and  the 
head  and  neck  of  the  os  femoris,  which  parts  are  enclos- 
ed in  a strong  capsular  ligament  arising  on  the  outer 
circumference  of  the  margin  of  the  acetabulum,  and 
inserted  into  the  root  of  the  neck  of  the  os  femoris. 
The  capsular  ligament  varies  in  its  thickness  at  different 


INFERIOR  EXTREMITIES. 


483 


places;  in  front  it  is  a fourth  of  an  inch  thick,  inter- 
nally it  is  somewhat  thinner,  and  posteriorly  where  it 
is  covered  by  the  quadratus  muscle  it  is  thinnest.  The 
surface  of  the  ligament  which  looks  towards  the  cavity 
of  the  joint,  is  reflected  somewhat  at  its  junction  with 
the  neck  towards  the  head  of  the  os  femoris,  and  forms 
regions  or  retinacula.  From  the  anterior  inferior 
spinous  process,  accessory  fibres  arise,  which  give  to 
the  capsule  an  increased  thickness  above. 

By  cutting  open  the  capsule,  we  see  that  its  internal 
face,  as  well  as  the  surfaces  of  the  bones,  are  covered 
by  a delicate  synovial  membrane;  that  a strong  liga- 
mentous cord  passes  from  one  side  of  the  notch  in  the 
lower  part  of  the  acetabulum  to  the  other,  leaving  an 
opening  below  for  the  introduction  of  vessels  into  the 
cavity  of  the  articulation. 

The  Ligamentum  Teres  arises  from  the  pit  in  the 
head  of  the  os  femoris,  and  seems  to  be  inserted  into 
the  bottom  of  the  acetabulum,  but  by  dissecting  the 
synovial  membrane  from  it,  its  insertion  into  the  ex- 
tremities of  the  notch  of  the  acetabulum  by  a bifurcated 
termination,  and  into  the  inferior  margin  of  the  cord, 
subtending  the  noteh,  will  be  seen. 

The  depth  of  the  acetabulum  is  increased  by  the 
cotyloid  ligament,  which  surrounds  its  margin,  and  is 
within  the  origin  of  the  capsular  ligament.  A quantity 


484 


OF  THE  LIGAMENTS. 


of  loose,  vascular,  adipose  matter,  fills  up  the  pit  in  the 
bottom  of  the  acetabulum,  and  is  covered  by  the  syno- 
vial membrane.  By  some  anatomists  it  is  called  the 
Gland  of  the  Hip  Joint. 

Of  the  Knee  Johit. 

The  Knee  Joint  is  formed  by  the  femur,  tibia,  and 
patella.  It  is  surrounded  by  an  imperfect  capsular 
ligament  which  is  very  thin  and  loose  on  each  side  of 
the  tendon  of  the  patella,  and  which  is  placed  in  con- 
tact with  the  fascia  of  the  lower  extremity,  where  the 
latter  is  continued  over  the  knee. 

The  External  Lateral  Ligament  arises  from  the 
tubercle  of  the  external  condyle,  and  is  inserted  into 
the  head  of  the  fibula.  The  internal  lateral  ligament 
arises  from  the  tubercle  of  the  internal  condyle,  and  is 
inserted  into  the  inner  side  of  the  head  of  the  tibia, 
being  continued  for  some  distance  down  the  internal 
side  of  the  bone.  The  front  of  the  joint  is  much  strength- 
ened by  the  ligament  which  passes  from  the  point  of 
the  patella  to  the  tubercle  of  the  tibia.  On  the  poste- 
rior face  of  the  capsular  ligament  is  found  an  irregular 
collection  of  fibres  passing  obliquely  from  the  upper 
back  part  of  the  external  condyle,  to  be  inserted  into 
the  back  of  the  head  of  the  tibia;  these  constitute  the 
Ligament  of  Winslow. 


INFERIOR  EXTREMITIES. 


485 


By  opening  the  joint  in  front,  so  as  to  let  the  pa- 
tella fall  upon  the  tibia,  a good  view  of  its  internal, 
arrangement  may  be  obtained.  The  synovial  mem- 
brane will  be  seen  arising  from  the  cartilaginous  mar- 
gin of  the  head  of  the  tibia,  and  around  that  of  the 
patella ; but  it  is  reflected  on  the  front  and  sides  of  the 
condyles  of  the  os  femoris  half  an  inch  or  more  above 
the  margin  of  its  cartilaginous  surface.  On  both  sides 
of  the  ligament  of  the  patella,  and  between  it  and  the 
synovial  membrane,  a large  mass  of  fat  is  found  filling 
up  the  vacuity  between  the  condyles  and  the  head  of 
the  tibia.  This  fat  projects  into  the  cavity  of  the 
articulation,  and  forms  on  each  side  of  the  patella  an 
oblong  ridge  covered  by  the  synovial  membrane.  It 
is  called,  on  the  outside  of  the  patella,  the  Ligamentum 
Alare  Minus,  and  on  its  inside,  the  Ligamentum  Alare 
Majus.  These  ligaments  terminate  each  in  a point  be- 
low the  patella  where  they  are  in  contact  with  each 
other;  and  from  this  place  a duplicature  of  synovial 
membrane,  ending  on  the  crucial  ligaments,  and  on  the 
os  femoris  between  its  condyles,  is  extended  to  the 
posterior  part  of  the  articulation. 

At  the  posterior  part  of  the  joint,  are  fixed  the 
Crucial  ligaments,  two  in  number,  the  Anterior  and  the 
Posterior.  The  first  arises  from  the  internal  face  of 
the  external  condyle,  and  is  inserted  in  front  of  the 
ridge  on  the  top  of  the  tibia,  its  fibres  being  partially 
blended  with  those  of  the  semilunar  cartilages.  The 


486 


OF  THE  LIGAMENTS. 


Posterior  arises  from  the  external  face  of  the  internal 
condyle  of  the  os  femoris,  and  is  inserted  into  the  head 
of  the  tibia  behind  the  ridge  on  its  top,  some  of  its 
fibres  being  blended  with  the  external  semilunar  car- 
tilage. These  ligaments  are  exterior  to  the  synovial 
membrane. 

The  Semilunar  Cartilages,  two  in  number,  are 
placed  between  the  tibia  and  the  os  femoris;  to  see 
them  well  the  last  bone  must  be  removed,  lea\ing  them 
on  the  tibia.  They  are  thick  at  their  exterior  cir- 
cumference and  are  brought  to  a thin  edge  internally ; 
are  fastened  to  the  capsular  ligament  by  their  outer 
margin,  but  the  internal  is  loose ; their  upper  and 
under  surfaces  are  covered  by  the  synovial  mem- 
brane. The  internal  is  longer  from  before  backwards 
than  transversely,  it  is  therefore  nearly  semi-circular; 
the  external  is  almost  circular,  in  each  of  which  cases 
they  exactly  conform  to  the  corresponding  articular 
surface  of  the  tibia.  The  posterior  end  of  both  of 
these  cartilages  is  fixed  to  the  tibia  between  the  spine 
on  its  top,  and  the  posterior  crucial  ligament;  their 
anterior  ends  are  inserted  into  the  tibia  before  the 
same  spine.  Occasionally  a transverse  ligamentous 
band  is  seen  to  unite  their  anterior  extremities. 

The  height  to  which  the  synovial  membrane  ascends 
above  the  patella,  should  be  noticed  by  the  student,  as 
well  as  a large  bursa  just  behind  the  tendon  of  the  ex- 


INFERIOR  EXTREMITIES. 


487 


tensor  muscles,  which,  most  commonly  communicates 
with  the  joint. 

Of  the  Peroneo-Tihial  Articulation. 

The  head  of  the  fibula,  where  it  is  united  to  the 
tibia,  has  all  the  apparatus  of  a moveable  joint.  The 
capsular  ligament  is  thickened  in  front  and  behind, 
which  occasions  the  names  of  Anterior  and  Posterior 
Ligaments.  But  this  joint  is  particularly  sti'ength- 
ened  by  the  insertion  of  the  external  lateral  ligament 
of  the  knee  and  by  the  tendon  of  the  biceps  muscle. 

The  Interosseous  Ligament  fills  the  interstice  be- 
tween the  two  bones.  It  is  attached  to  the  interosseous 
ridges  which  lie  on  their  opposing  surfaces  and  runs 
the  greater  part  of  their  length.  It  consists  of  oblique 
fibres  going  from  one  bone  to  the  other,  and  forming  a 
thin  strong  membrane.  Just  below  the  head  of  the 
tibia  it  is  perforated  by  a large  foramen  which  trans- 
mits the  tibialis  posticus  muscle  and  the  anterior  tibial 
artery  and  vein;  near  the  ancle  joint  it  is  perforated 
also  by  the  fibular  artery. 

The  Tibia  and  Fibula  are  united  at  the  ancle  joint 
by  triangular  surfaces,  concave  on  the  part  of  the  tibia, 
and  convex  on  the  part  of  the  fibula.  These  surfaces 
are  held  together  by  intermediate  ligamentous  matter, 


488 


OF  THE  LIGAMENTS. 


as  well  as  a ligament  expanded  on  the  front  and 
back  of  the  junction  called  the  Anterior  and  the  Pos- 
terior Ligaments.  The  cartilaginous  crust,  on  the 
ends  of  the  tibia  and  the  fibula,  belonging  to  the  ancle 
joint,  are  continued  for  a line  or  two,  on  the  opposed 
surfaces  of  the  tibia  and  the  fibula. 

Of  the  Ancle  Joint. 

The  Ancle  Joint  is  formed  by  the  tibia,  fibula,  and 
astragalus.  The  capsular  ligament  is  extremely  thin, 
and,  indeed,  has  no  very  evident  existence  before  and 
behind;  the  fatty  matter  which  surrounds  the  joint,  is 
in  immediate  contact  with  the  synovial  membrane,  and 
protrudes  it  in  some  places,  inwards,  towards  the  ca- 
vity of  the  articulation. 

There  are  very  strong  lateral  ligaments  on  both 
sides.  The  Deltoid  arises  from  the  inferior  extremity 
of  the  malleolar  process  of  the  tibia,  and  by  radiating 
considerably,  is  inserted  into  the  internal  side  of  the 
os  calcis,  and  astragalus.  The  ligaments  on  the  exter- 
nal side  of  the  ancle  are  divisible  into  three  fasciculi. 
The  Anterior  arises  from  the  anterior  part  of  the  end 
of  the  malleolus  externus,  and  passes  obliquely  for- 
wards to  be  inserted  into  the  upper  and  outer  part  of 
the  astragalus.  The  Middle  Ligament,  or  Fasciculus, 
arises  from  the  extremity  of  the  fibula,  and  descends 
perpendicularly  to  be  inserted  into  the  outside  of  the 


INFERIOR  EXTREMITIES. 


489 


os  calcis.  The  Posterior  Ligament  comes  from  the 
back  of  the  extremity  of  the  malleolus  externus,  and 
passes  very  obliquely  to  be  inserted  into  the  outer  back 
part  of  the  astragalus. 

On  cutting  open  this  joint,  it  will  be  seen  that  the 
synovial  membrane  is  connected  to  the  several  bones  at 
the  margins  of  the  cartilaginous  articular  surfaces. 

Ligaments  of  the  Foot. 

The  os  calcis  and  the  astragalus  are  united  by  liga- 
ments investing  their  articulating  surfaces;  the  syno- 
vial capsule  belonging  to  their  posterior  surface  is  in- 
sulated, but  the  anterior  is  extended  into  that  which 
unites  the  os  astragalus  and  the  naviculare.  Between 
the  two  bones  there  is  a very  strong  ligament  arising 
from  the  fossa  of  one  to  be  inserted  into  the  fossa  of  the 
other ; it  is  their  strongest  means  of  union. 

The  Naviculare  and  the  Astragalus  are  united  by 
a capsular  ligament  with  its  synovial  membrane.  This 
capsule  is  thickened  by  additional  slips  above  and  in- 
ternally ; the  whole  arrangement  of  the  joint  is  such  as 
to  admit  of  much  motion. 

The  Os  Calcis  and  Cuboides,  besides  their  capsular 
ligament  and  synovial  membrane,  have  an  acces- 

3 Q 


490 


OF  THE  LIGAMENTS. 


sion  of  fibres  called  Superior,  Lateral,  and  Inferior 
Ligaments. 

A very  strong  ligament  passes  from  the  anterior  in- 
ternal part  of  the  os  calcis,  and  is  fixed  into  the  tuber- 
cle on  the  under  surface  of  the  scaphoides.  This  li- 
gament supports  the  astragalus. 

There  are  many  other  strong  ligaments  connecting 
the  bones  of  the  tarsus  together;  their  course  is  varied 
and  complicated.  Besides  which  there  are  capsular 
and  synovial  membranes  to  the  several  opposed  articu- 
lar surfaces  of  hones. 

The  Ligaments  of  the  Metatarsus  and  of  the  Pha- 
langes correspond  so  nearly  with  those  of  the  meta- 
carpus and  the  phalanges  of  the  fingers,  that  the 
reader  is  referred  to  the  account  of  the  Ligaments  of 
the  Hand. 


PART  V. 


Of  the  Skin,  Hair,  JStails,  and  Sebaceous  Organs. 


CHAPTER  I. 

Of  the  Skin. 

The  Skia  consists  of  Cuticle,  Corpus  Mucosum,  and 
the  Cutis  Vera.  These  parts  are  easily  separated  from 
each  other  by  maceratioii ; and  by  boiling  or  immersion 
into  hot  water  for  a few  minutes,  and  immediately 
afterwards  throwing  the  part,  thus  heated,  into  cold 
water.  Vesicatories  also,  applied  to  the  living  body, 
cause  the  cuticle  to  detach  itself  from  the  parts  below. 

The  Cuticle  is  a very  thin  semitransparent  mem- 
brane, distributed  over  almost  the  whole  surface 
of  the  body.  In  some  parts  it  is  from  birth  much 
thicker  than  in  others,  as  in  the  palms  of  the  hands  and 
the  soles  of  the  feet,  and  from  friction  and  pressure  in 
after  life,  it  increases  further  in  its  proportionate  thick- 


492 


OF  THE  SKIN. 


ness.  The  cuticle  presents  every  where,  but  more 
obviously  in  the  hands  and  feet,  a multitude  of  fur- 
rows caused  by  the  surface  of  the  cutis  vera,  and  which 
are  arranged  in  straight,  curved,  or  spiral  lines.  It 
adheres  by  filaments  to  the  cutis  vera,  and  is  perforat- 
ed by  the  exhalent  or  perspiring  pores,  by  the  ex- 
cretory ducts  of  the  sebaceous  glands,  by  the  hairs, 
and  according  to  some  anatomists  by  the  origin  of  ab- 
sorbent vessels.  These  perforations  are  best  seen  on 
the  nose,  ears,  external  parts  of  generation,  the  palms 
of  the  hands,  and  the  soles  of  the  feet.  From  the  in- 
ternal surface  of  the  cuticle  processes  are  sent  in, 
which  line  the  difierent  foramina  of  the  cutis  vera. 
When  the  cuticle  is  raised  by  a blister  these  processes 
become  collapsed,  by  which  their  sides  are  approxi- 
mated, and  the  fluid  effused  beneath  is  prevented  from 
escaping. 

The  cuticle  has  but  little  elasticity,  no  vascularity, 
and  no  sensibility.  Its  use  seems  to  be  to  diminish 
evaporation  from  the  surface  of  the  body,  and  to  shield 
the  pulpy  terminations  of  the  nerves  of  the  cutis  vera. 

The  Corpus,  or  Rete  Mucosum,  is  the  second  layer 
of  the  skin,  and  on  it  depends  the  great  variety  of 
colours  observed  in  the  human  species.  It  covers 
every  part  of  the  cutis  vera  except  under  the  nails. ^ 

* It  is  probable,  however,  that  it  exists  even  there,  but  it  is  not 
so  obvious  as  elsewhere. 


OF  THE  SEIN. 


493 


Its  consistence  is  mucilaginous,  from  which  its  name  is 
derived. 

Mr.  Gaultier  states  that  on^  the  soles  of  the  feet  in 
negroes,  the  corpus  mucosum  is  seen  to  he  disposed  in 
the  following  manner : 1st.  On  the  inequalities  of  the 
cutis  vera,  next  to  its  papillae,  there  is  a layer,  which 
he  calls  bloody  pimples,  (bourgeons  sanguins)  but 
which,  in  the  opinion  of  other  anatomists,  are  only  the 
papillae  of  the  cutis  vera.  2d.  Next  to  them  is  a 
layer,  called  Albida  Profunda,  on  account  of  its  con- 
stant colour  and  situation.  3d.  Then  small  points, 
constituting  a layer,  placed  over  the  last,  of  a very 
dark  brown,  in  negroes,  which  he  calls  Gemmula.  And 
4th,  a layer  adjacent  to  the  cuticle,  spread  over  the 
last,  and  called  Albida  Superficialis,  also,  from  its 
colour  and  position. 

In  cutting  through  the  skin,  from  the  heel  to  the 
toes,  at  right  angles  to  its  furrows,  in  negroes,  this 
arrangement  may  be  readily  recognized.  And  in  cases 
where  it  has  been  rendered  indistinct  from  sickness 
it  may  be  improved  by  immersing  the  skin  for  three 
or  four  days  in  lime  water,  a solution  of  potash  or 
barytes,  and  afterwards  keeping  it  the  same  length  of 
time  in  a solution  of  corrosive  sublimate. 

Mai’jolin  Man.  d’Anat.  vol.  ii.  p.  587.  Bichat  Anat.  Gen. 
Paris,  1818,  vol.  ii.p.  703. 


494 


OF  THE  SKIN. 


The  existence  of  this  arrangement  of  the  corpus 
mucosum  may  be  established  in  other  parts  of  the  body 
by  the  elfects  of  blisters.  The  fluids  being  thus 
locally  attracted,  infiltrate  the  corpus  mucosum  and 
separate  its  layers,  in  part,  in  order  to  form  a vesicle, 
frequently  very  thick,  particularly  in  fat  persons. 

The  Cutis  Vera  gives  a covering  to  the  whole  body. 
It  consists  of  fibres  variously  blended  and  running  in 
every  direction.  Its  blood-vessels  and  nerves  are  so 
numerous  that  the  prick  of  the  finest  needle  in  any 
part  will  occasion  pain  and  produce  blood.  Its  inte- 
rior surface  is  in  close  connexion  with  the  subjacent 
cellular  and  adipose  membrane,  from  which  it  may  be 
imperfectly  separated  by  dissection.*  The  cutis  vera 
is  extremely  elastic.  Its  thickness  varies;  on  the  back, 
on  the  soles  of  the  feet,  and  on  the  palms  of  the  hands 
it  is  thicker  than  elsewhere.  On  the  lips  and  on  the 
margin  of  the  anus  it  is  very  thin. 

The  cutis  vera,  on  its  external  face,  is  divided  by 
numerous  lines  running  in  different  directions.  When 
the  cuticle  is  removed,  this  surface  is  seen  to  be  stud- 
ded with  papillm  which  are  extremely  sensitive  and 
vascular,  and  which  as  mentioned,  are,  by  some,  consid- 
ered as  the  same  with  the  projections  termed  Bour- 
geons Sanguins,  by  Mr.  Gaultier,  though  he  views  the 

* Maceration  is  a mnch  more  complete  way  of  effecting  this 
separation. 


OF  THE  HAIR. 


495 


latter  as  the  first  layer  of  the  rete  raucosuin  and  the 
papillae  as  entirely  distinct.  They  are  very  obvious 
on  the  palms  of  the  hands  and  on  the  soles  of  the  feet, 
where  they  are  arranged  in  double  rows  on  the  ridges 
of  the  cutis  vera. 


CHAPTER  II. 

Of  the  Hair. 

The  Hair  grows  in  the  cellular  membrane  beneath 
the  skin.  It  is  best  studied  on  the  mustachios  of  the  lar- 
ger animals,  as  the  horse,  ox,  and  so  on.  Around  the 
root  of  each  hair  there  are  two  capsules,  one  within 
the  other.  The  internal  is  very  vascular,  and  the 
blood  reaches  it,  not  from  the  bottom,  but  near  the  sur- 
face of  the  cutis.  In  the  root  of  the  hair  there  is  a 
hollow  canal  filled  with  a pulpy  substance. 


496  OF  THE  SEBACEOUS  ORGANS. 

CHAPTER  III. 

Of  the  jVails. 

The  Nails  are  fibrous,  a continuation  of  the  cuticle, 
but  are  indebted  for  their  growth  to  their  adhering  by 
their  roots  and  under  surface,  to  the  cutis  vera.  If 
they  are  torn  off  by  pincei’s  or  separated,  by  macera- 
tion, their  form  and  origin  may  be  readily  seen. 


CHAPTER  1\. 

Of  the  Sebaceous  Organs. 

They  consist  of  follicles  and  glands.  The  follicles 
are  placed  around  the  roots  of  the  hair  in  the  interior 
of  the  capsules.  They  secrete  an  unctuous  fluid 
which,  by  inspissation,  becomes  of  the  consistence  of 
suet.  Being  seated  under  the  skin  they  are  more 
abundant  in  some  parts  than  in  others,  as,  for  exam- 
ple, in  the  nose,  ears,  groins,  and  external  parts  of 
generation. 

The  Sebaceous  Glands  are  about  the  size  of  millet 
seeds,  and  are  placed  also  under  the  cutis  vera.  They 
are  particularly  numerous  under  the  skin  of  the  mons 


veneris. 


INDEX 


Abbomejt, 

Page 

189 

muscles  of. 

190 

contents  of, 

218 

Accessory  Nerve, 

109 

Adductors  of  Thigh, 

414 

Adductor  Oculi, 

113 

Ankle  Joint, 

448 

Aorta, 

178 

Aponeurosis  Pelvica, 

288 

Aqueduct  of  Ear, 

137 

Articular  Arteries, 

446 

Arm,  Muscles  of. 

359 

Arteries  of. 

387 

Arteries  of  Neck  and  Head 

29 

Arbor  Vitae, 

62 

Auditory  Nerve, 

105 

Auricular  Artery, 

32 

Back,  Muscles  of. 

339 

Biceps  Flexor  Cubiti, 

-358 

Bladder, 

262 

Brain, 

50 

Blood  vessels  ofv 

74 

Brachial  Artery, 

383 

Bronchia, 

• 182 

Bronchial  Glands, 

184 

Bronchial  Arteries, 

325 

Buccinator, 

8 

Carotid  Arteries,  . 29,  30, 35 

Cava  Ascendens, 

335 

Carunculae  Myrtiformes, 

303 

Cardiac  Nerves, 

317 

Cervical  Artery, 

36 

Cervical  Nerves, 

48 

Cervicalis  Descendens, 

340 

Cerebrum, 

54 

Cerebellum, 

61, 80 

Choroides, 

119 

Chorda  Tympani, 

139 

Ciliary  Ligament,  . 

121 

Ciliaris, 

4 

Circumflex  Iliac  Arteries, 

336 

Circumflex  Art.  of  Arm, 

385 

Clavicle,  Articulation  of. 

476 

Clitoris, 

297 

Coeliac  Artery, 

Page 
. 326 

Commissures  of  Brain, 

83,  59,  88 

Compressor  Naris, 

89,  90,  91 

<r> 

• 

Complexus, 

348 

Convolutions  of  Brain, 

94 

Coronary  Arteries, 

179 

Veins, 

179 

Cornea, 

118 

Corpus  Callosum,  . 

56 

Corpus  Cavernosum, 

269 

Corpus  Spongiosum, 

270 

Corpusculum  Arantii, 

175 

Corrugator  Supercilii, 

5 

Cremaster, 

198 

Crural  Nerves, 

457 

Crural  Arch, 

215 

Crural  Ring, 

215 

Cutaneus  Internus, 

399 

Cutaneous  Nerves  of  Thigh, 

■455 

Dartos, 

275 

Deltoides, 

355 

Depressor  Lab.  Sup.Alseque 
Nasi,  . . ... 

6 

Depressor  Anguli  Oris, 

7 

Depressor  Labii  Infer, 

7 

Digastricus, 

16 

Diaphragm, 

253 

Dura  Mater,  , 

• 

51 

Ear, 

127 

Elbow  Joint, 

478 

Emulgent  Arteries, 

328 

Epididymis, 

* 

279 

Epigastric  Artery,  . 

209, 

334 

Epiglottis, 

, 

160 

Extremities  Upper, 

353 

Extremity  Upper,  Arteries  of. 

382 

Extensor  Muscles  of  Fore  Arm, 

369 

Eye, 

Thumb, 

373 

no 

Muscles  of. 

no, 

112 

Eyelids, 

111 

Eye  Ball, 

117 

498  INDEX. 


Page 

Fascia  Superf.  Cervicis, 

10 

Profunda, 

12 

Sujjerf.  Abdom. 

201 

Traiisversalis, 

206 

Femoris, 

211 

Iliaca 

212 

of  Upper  Extr. 

353 

of  Lower  Extr. 

406 

Plantaris, 

432 

Facial  Artery, 

31 

Fallopian  Tubes, 

307 

Fauces, 

147 

Femoral  Sheath, 

216 

Arteries,  . 

440 

Hernia, 

. 210 

Flexors  of  Fore  Arm, 

>363 

Foramen  of  Winslow, 

225 

Fourchette, 

299 

Foot,  Arteries  of,  . 

451 

Muscles  of. 

451 

Ligaments  of, 

489 

Hair, 

495 

Hand,  Arteries  of,  . 

393 

Muscles  of,  . 

375 

Articulations  of. 

481 

Hamstring  Muscles, 

420 

Heart, 

170 

Head  and  Neck, 

1 

Hepatic  Duct, 

241 

Hip  Joint, 

482 

Hyo-Glossus, 

19 

Hypoglossal  Nerve, 

43,  70 

Hyoides, 

153 

Hymen, 

300 

Humours  of  Eye, 

122,  124 

lliacus  Internus, 

258 

Iliac  Arteries, 

330,  33 

Intestinal  Canal, 

23 

Internal  Maxillary  Artery, 

33 

Infundibulum, 

65 

Intercostal  Muscles, 

165 

Arteries, 

325 

Inguinal  Hernia, 

201 

Interspinules, 

351 

Intertransversarii,  . 

351 

Intercosto  Hunier.al  Nerves 

> 

404 

Inferior  I'hyroid  Artery, 

35 

Interpubic  Ligament, 

287 

Intercostal  Artery,  Superior 

325 

Interosseal  Artery, 

391 

Irfs, 

120 

Jugular  Veins, 

36 

Page 

Kidmes, 

247 

Knee  Joint, 

484 

Labia  Externa, 

296 

Labyrinth,  . 

134 

Lachrymal  Gland,  . 

112 

Lachrymal  Ducts,  . 

111 

Sac, 

112 

Larynx, 

153 

Cartilages  of,  . • 

154 

Muscles  of. 

158 

Laryngeal  Nerve,  . 

45 

Lateral  Ventricles, 

57 

Latissimus  Dorsi, 

341 

Lungs,  , 

180 

Leg,  Muscles  of. 

422 

Nerves  of. 

463 

Lenticular  Ganglion, 
Levator  Labii  Slip.  Alsque 

127 

Nasi, 

5 

Levator  Anguli  Oris, 

5 

Levator  Scapula:, 

343 

Ani, 

291 

Levatores  Costarum, 

352 

Lingualis  Musculus, 

19 

Lingual  Artery, 

30 

Ligaments, 

456 

of  Jaw, 

466  • 

Spine, 

467 

Thorax, 

470 

Pelvis, 

472 

Upper  Extremity, 

475 

Lower  Extremity, 

482 

Liver, 

Blood  vessels  of. 

235 

238 

Longus  Colli, 

19 

Longissinius  Dorsi, 

345 

Lower  Extremity,  Muscles  of. 

409 

Arteries  of. 

440 

Lower  Extremity,  Nerves  of. 

454 

Veins  of. 

452 

Lumbar  Arteries, 
Lymphatics  of  Neck, 

329 

28 

Mammary  Artery,  . 384, 

324 

Masseter, 

9 

Mammie, 

309 

Medulla  Oblongata,  6f 

, 79 

Mediaslina,  . 168, 

ISO 

Mesentery, 

226: 

Mesocolon, 

227 

Mesenteric  Arteries,  327, 

329 

Median  Nerve, 

401 

Slotores  Extern!,  . 

68 

* 

, -x;  ' • 

INDEX. 

4998 

Page 

Page  '7^ 

Mouth 

144 

Platysma  Myoides 

11 

Multifidus  Spihae  ■ . . 

349 

Pleura 

167 

Musculo  Cutaneus  N. 

400 

Plexus  Axillary 

49 

Mylo  Hyoideus 

18 

Solar 

■ 321  ,-m 

Lumbalis 

454  . 

Nails 

■ 496 

Ischiadicus 

458  ' 

Nose 

140 

Pons  Varolii 

63 

Nerves  of. 

143 

Popliteal  Artery 

‘445  V 

Nymph^e  . . 

298 

Portio  Dura  N. 

. 38, 69  ;■ 

Mollis  N. 

138,  139 

Obturator  Muscles 

419 

frostate  Gland 

266 

Occipito  Frontalis  i 

2 

Psoas  Parvus 

257  ■ 

Obliquus  Esternus 

192 

Magnus 

. 257 

Internus 

194 

Pterygoideus  Externus 

. 22 

Capitis 

351 

Internus 

22 

Occipital  Artery 

31 

Pulmonary  Artery 

175  > 

(Esophagus 

151 

Pubic  Ligament 

200 

(Esophageal  Artery 

325 

Pyramidalis 

197 

Olfactory  Nerve 

66,  142 

Omenta  . . 224,  226 

Quadratus  Lumborum 

259  •• 

Orho  Hyoideus 

16 

Orbicularis  Oris 

8 

Radial  Artery 

388  •. 

Orbicularis  Palpebrarum 

4 

Nerve 

400 

Orbit,  Vessels  and  Nerves  of,  125 

Rectus  Femoris 

410 

Optic  Nerve 

66 

Rectus  Abdominis 

196 

Os  Tines 

305 

Rectvis  Capitis 

20,  350 

Ovaries  . . ■ ■ 

307 

Rectum 

261 

Renal  Capsules 

251 

Pancreas 

245 

Retina 

121 

Palate,  Soft 

147 

Rhomboideus 

343 

Muscles  of  . ■ 

148 

Papills  of  Tongue 

145 

Sacro  Lumbalis 

345 

Parotid  Gland 

24 

Sartorius 

409 

Par  Vagum  Nerve 

315 

Saphena  Vein 

. - 452 

Par  Vagum  . ,, 

45 

Scaleni  Muscles 

2 

Pectoralis  Major 

163 

Scapula,  Muscles  of 

356 

Minor 

164 

Scapular  Artei-ies  . 

385 

Pelvis  Male 

260 

Sciatic  Nerve 

461 

Female 

295 

Sclerotica 

118 

Pelvis  Arteries  of  . 

331 

Scrotum 

275 

Penis 

268 

Sebaceous  Glands 

496. 

Pericardium 

169 

Semi-spinalis  Colli 

348 

Peritoneum 

222 

Dorsi 

349 

Perineum  . 281, 285,  292 

Seminal  Vesicles 

267 

Muscles  of 

282 

Serratus  Major 

165 

Peroneal  Artery  , . 

449 

Serrati  Postici 

342,  343 

Peroneo-Tibial  Articulation 

487 

Shoulder,  Articulations  of 

475 

Pharynx 

149 

Skin 

491 

Pharyngeal  Artery 

31 

Spermatic  Cord 

280 

Phrenic  Nerve 

48,  314 

Spermatic  Artery 

328 

Artery 

326 

Spleen 

. ■ 242 

Pia  Mater 

54 

Sphincter  Ani 

284  1 

Pineal  Gland 

60,  93 

Vagins 

302  . 

1’ituitary  Gland 

65,  93 

Spinal  Marrotv 

71,  77 

500 


INDEX. 


Spinalis  Dorsi 
Splanchnic  Nerve 
Splenius 

Sterno-Cleido  Mastoideus 
Sterno  Hyoideus 

Thyroideus 

Stomach 

Stylo-Glossus 

Hyoideus 
Pharyngeus 
Subclavius 
Subclavian  Artery 
Submaxillary  Gland 
Sublingual  Gland 
Sympathetic  Nerve  46, 

Temporal  Artery 
Temporal  Muscle 
Tensor  Tarsi 
Tensor  Femoris 
Testicles 

Coats  of 
Third  Nerves 
Thigh,  Muscles  of  . 

Arteries  of  . 
Thorax 

Muscles  of 
Thorax,  Viscera  of 
Thoracic  Duct 
Thymus  Gland 
Thyreo  Hyoideus 
Thyroid  Gland 
Artery 
Veins 
Tibial  Artery 
Tongue 
Trachea 

Trachelo  Mastoideus 


Page 

Page 

346 

Transversalis  Cervicis 

347 

321 

Abdominis 

196 

344 

Perinei 

283 

12 

Trapezius 

339 

15 

I'riangular  Ligament 

285,  292 

15 

Triangularis  Sterni 

165 

227 

Trigeminus  Nerve 

. 39,68 

17 

Trochleares 

67 

17 

Trunk,  Nerves  and  Vessels  of  314 

17 

Veins  of 

335 

163 

Tunica  Arachnoidea 

. 53 

324 

Tympanum  . 

130 

26 

Bones  of 

132 

27 

Muscles  of 

133 

317,  323 

• 

Ulnar  Artery 

390 

. 33 

Nerve 

403 

9 

Upper  Extremity 

353 

114 

Arteries  of  ’ 

382 

4ip 

Veins  of 

394 

275 

Nerves  of 

397 

277 

Ureters 

250 

67 

Urethra  of  Male 

271 

409 

of  Female 

299 

440 

163 

Uterus 

303 

163 

Vagina 

300 

165 

Valve  of  Brain 

61 

, 337 

of  Bauhin 

234 

185 

Vasti 

411 

16 

Vas  Deferens 

278 

23 

Vertebral  Arteries 

35 

30 

Vestibulum 

298 

37 

Vulva 

296 

447^444 

144 

Wrist  Joint 

479 

182 

Zygomaticus  Major 

6 

347 

Minor 

6 

/i 

L, 

1 V 


■■  - 


0 


*jSf*  : 1 


ml 


■'jjHorner  ■ 

: 1827 


